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OVERVIEWThis application note shows how to use a PIC16C923microcontroller to control operation of the CS5460power measurement integrated circuit from CirrusLogic/Crystal Power Measurement, to drive a liquidcrystal panel (glass), and to store and retrieve datausing the 24C01 Serial EEPROM.Energy transferred between the line and load is mea-sured by the CS5460. The PIC16C923 initializes theCS5460 with calibration data stored in the 24C01Serial EEPROM, records the total energy measured inthe 24C01, and displays results on the LCD panel.

INTRODUCTIONMost forms of AC power measurement have alreadybeen patented by various companies, so measuringAC power in a product intended for sale often involvespaying licensing fees to another company. TheCS5460 offers an integrated solution that provides apower and energy measurement sub-system, requir-ing only voltage and current sense inputs. In addition,calibration is accurate for any current waveform orpower factor that may be encountered.By using the CS5460, a PIC16C923 microcontroller, a24C01 Serial EEPROM, and an LCD panel, a simpleand compact device is constructed that displays RMSvoltage, RMS current, and the energy consumed by aload. These features are extended by including com-putation and display of apparent power, true power,and power factor.The PIC16C923 LCD controller can drive an LCD panelwith up to 4 common planes and up to 32 segments. 4Kwords of program memory, and 176 bytes of RAM areprovided. A Synchronous Serial Peripheral (SSP) pro-vides SPITM communications with the CS5460.Inter-Integrated CircuitTM (I2C) communications with the24C01 Serial EEPROM are provided by firmware.

FIGURE 1: WATT-HOUR METER

HARDWAREOn power-up, the PIC16C923 microcontroller readsthe calibration data, device serial number, and totalenergy from the 24C01, writes the calibration data tothe CS5460, initializes the CS5460, and reads thestate of the control buttons. If the control button state matches one of three pat-terns at RESET, a control mode is entered that allowssetting the real time clock (RTC), clearing the totalWHr and restoring default calibration values, or adjust-ing calibration constants.During normal operation, the PIC16C923 countspulses from the CS5460, reads CS5460 data regis-ters, drives the LCD panel to display the requesteddata, and monitors the control buttons. The pulses areused to update the total energy count and are periodi-cally written to the 24C01.The CS5460 measures line voltage and line current tocompute power and energy transferred on the line.When a unit of energy has transferred between theline and the load, a pulse with direction indication isgenerated.

Authors: Brett Duane, Stephen HumberdMicrochip Technology Inc.

Watt-Hour Meter using PIC16C923 and CS5460 2000 Microchip Technology Inc. DS00220A-page 1

The CS5460 power/energy measurement IC mea-sures instantaneous voltage and current four thousandtimes a second and uses these measurements tocompute VRMS, IRMS, instantaneous power, and accu-mulated energy results for read out. In addition, apulse is generated whenever a user specified amountof energy transfers between the line and the load.

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FIGURE 2: SYSTEM BLOCK DIAGRAM

CS5460 Power/Energy Measurement CircuitThe CS5460 measures the instantaneous line voltageand line current, four thousand times a second. Thesemeasurements are used to compute instantaneouspower, energy transferred since the last measurement,RMS voltage, RMS current, and accumulated energytransferred. All measurements and results can be readby an external controller, via the SPI interface. A trans-fer of energy is also indicated by a pulse output at theEOUT pin. The direction of transfer is indicated by theEDIR pin.Communication with the CS5460 takes place over a4-wire SPI link with the PIC16C923. The CS5460 isconfigured and controlled over this link. Calculationresults are also read by the controller over this link.The line voltage may be sampled using a transformeror resistor divider. The differential input is limited to150mVRMS. In this application, line voltage is detectedfrom the secondary winding of the power supply trans-former, T2 (see Figure 3B and Figure 5). When oper-ating from 120V, there is about an 8V peak at VIN+ orVIN-. When operating from 220V, there is about a14.7V peak. This voltage is further reduced by a resis-tor network before being applied to the CS5460 (seeFigure 4A).The line current may be sampled using a currenttransformer or shunt resistor. Depending on the gain ofthe input channel, the differential input is limited toeither 30 mVRMS (gain = 50), or 150 mVRMS(gain = 10). In this application, the current channelgain is 10, for a maximum input voltage of 150 mVRMS.This voltage is provided by the current sense trans-former T1 and resistor R21, and is reduced by a resis-tor network similar to the line voltage channel (seeFigure 3A and Figure 4B).

There is no switching provided, or required for opera-tion from either 120V or 220V, 50Hz or 60Hz. How-ever, accuracy will decrease when operating from aline voltage different than the calibration conditions.By using the instantaneous voltage and current, theCS5460 computes the RMS voltage, RMS current,and instantaneous power. The instantaneous power isintegrated at the sampling rate (4000Hz) to computethe energy transferred. A new RMS value is availableevery 4000 samples. Samples are taken 4000 timesper second, or about 67 times per 60Hz cycle.When the integrated energy exceeds 10 WSec, a fixedwidth pulse is generated at the EOUT pin and the inte-grated energy is reduced by 10 WSec. These pulsesare counted to record energy consumption. The EDIRpin indicates the direction that the energy flows (reac-tive loads can return energy to the line). Depending onthe state of the EDIR pin, the pulse at the EOUT pincauses the PIC16C923 to either increment, or decre-ment the total energy count.

FIGURE 3: CIRCUITS THAT MONITOR LINE CURRENT (A) AND LINE VOLTAGE (B)

CURRENT LNG

LNG

CS5460

BUTTONS LCD

VOLTAGESENSE

24C01 PIC16C923

SENSE

SOURCE LOAD

GROUND

NEUTRAL

LINE

T2

T1

R21IIN+

VIN+

VIN-

LINE

NEUTRAL

3A

3B

D1

D2

56, WDS00220A-page 2 2000 Microchip Technology Inc.

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FIGURE 4: CS5460 INPUT ATTENUATION

CIRCUITS

Power SupplyA transformer isolated power supply provides powerfor the Watt-Hour Meter. The transformer primary isconnected to the line between the power source andthe current sense transformer. The AC voltage fromthe transformer secondary is used to detect the linevoltage and is coupled to the CS5460 through a resis-tor network (see Figure 4A).The AC from the center tapped secondary is full waverectified, filtered, and provided to the 5V regulator. The5V loads are the power-on LED, the CS5460, andthe PIC16C923. The majority of the current is drawnby the LED, about 7.5mA. The rest of the circuit drawsless than 5mA.

FIGURE 5: POWER SUPPLY CIRCUIT

PIC16C923 MicrocontrollerThe PIC16C923 microcontroller provides a LiquidCrystal Display (LCD) driver module that drives theLCD panel directly. It also communicates with theCS5460 using the 4-wire SPI link (SDI, SDO, SCL,and CS) to issue commands, write calibration data,and read measurement and calculation results. Themicrocontroller also controls the CS5460 RESET line(see Figure 6).The controller system oscillator is driven by theCPUCLK output of the CS5460 and operates at4.096MHz. The system oscillator is configured for XTmode, but any crystal mode will work. A 32.768kHzcrystal has been provided for use with the Timer1oscillator. Since the CS5460 provides a 4.096MHzclock source to the PIC16C923, either source can beused for the real time clock source. The demonstrationunits have been configured to use the CS5460 clocksource for the real time clock.

FIGURE 6: CONNECTIONS BETWEEN THE CS5460 AND THE PIC16C923

R11

VIN-R12

VIN+R10 R25

C24C25

9 VIN+

10 VIN-R23

C15 CS5460

4A

CS5460R9

R20

15 IIN-

IIN+R22

C14

4B

IIN+ 16

100k

100k

1k

301

301

0.01F 0.01F

4700pF

0.015F

180k

10k

301

T2VIN+

VIN-

LINE

NEUTRAL C13 C12

D1

D2

78L05I

GO +5V

U4

0.1F1000F

C21

+5V

SDO

EDIR

EOUT

RESET

CS

CPUCLK

SCLK

SDI

CS

RESET

SCLK

SDO

CPUCLK

SDI

EDIR

EOUT

NC

10

12

13

14

15

16

2425

9 8 7

PIC16C923

RA4RB1

RB0

RC3RC4RC5OSC1OSC225

RA2

U1

22

23

21

19

241

CPUCLKSDI

XIN

EDIR

EOUTRESET

SDO

SCLK

CS

XOUT2

5

6

7

U2CS5460

R19

4.096MHZ

0.1F

10k 2000 Microchip Technology Inc. DS00220A-page 3

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Interface to 24C01 Serial EEPROMThe Serial EEPROM stores the calibration constantsrequired by the CS5460 for accurate measurements,and the total accumulated energy transferred. Thecontroller communicates with the 24C01 via an I2Cinterface. Since the SSP module is already in use sup-porting SPI communications with the CS5460, thePIC16C923 must perform I2C communications in firm-ware, using RA0 (SCL) and RA1 (SDA) (see Figure 7).Either the 24C01, or the PIC16C923, may pull theSDA line low, depending on the direction of the dataflow. Since the PIC16C923 always drives the SCL line,no pull-up resistor was included. A memory map of theSerial EEPROM is included in Appendix A.

FIGURE 7: CONNECTION BETWEEN THE 24C01 AND THE PIC16C923

User InterfaceThe user interface consists of the LCD display, fourcontrol push buttons, one reset push button, and thepower-on LED.The PIC16C923 LCD module directly drives the LCDpanel. The panel can display eight, 7-segment digits(numbers only), seven decimal points and three colons.When pushed, each of the four push buttons pull therespective port pin low. The buttons are connected toPORTB and are numbered from 1 to 4, left to right.

FIRMWAREThe CS5460 transfers data in 4 byte groups (32-bits).The first byte contains the register address and a bitspecifying a read or write operation. The remaining 3bytes are transferred to or from one of the internal reg-isters. The CS5460 also accepts single byte com-mands. Such commands are followed by 3 SYNCbytes that are treated as NOP bytes.A write command is followed by 3 bytes of data to theCS5460, to be written to the selected register. A readcommand causes the 3 bytes of the selected registerto be output by the CS5460. If the command byte specifies an operation to be per-formed, or a read operation, the remaining 3 bytestransmitted by the PIC16C923 should be SYNC0bytes (0xFE).

Power-up and RESETA Power-on Reset initializes the CS5460 and clearsthe real time clock. Initialize On-Chip PeripheralsTimer1, Timer2, the SSP, and Ports A, B, and C areconfigured for operation. Interrupts are also enabled.The LCD module is then configured.Clear the LCD DisplayAll segment data registers are cleared to blank the dis-play. This routine is called frequently during normaloperation.Initialize VariablesIf this was a cold start (power has just been applied),the memory contents are cleared and the calibrationconstants are copied from the 24C01 to the CS5460.The device serial number and the current total WHrare retrieved from the 24C01. If a warm start hasoccurred, only the serial number is retrieved.Initialize the CS5460The CS5460 is configured to generate a pulse at theEOUT pin for each 10 WSec measured (360 pulsesper WHr). For 100W loads, this causes 10 pulses persecond to be generated.Check Button StatusThe status of the four push buttons is checked. If allfour buttons are pressed, the total WHr value in the24C01 is cleared and calibration values are copiedfrom the EEPROM to the CS5460. If the center twobuttons are pressed, the real time clock is set. If theouter two buttons are pressed, the Watt-Hour meterenters Calibration mode (see Table 1). If no buttonsare pressed, the CS5460 begins continuous measure-ments. Execution proceeds to the scrolling start-upmessage.

TABLE 1: BUTTON STATES CHECKED DURING RESET

Display the Start-up MessageA start-up message is displayed on the LCD. Thismessage scrolls across the display until any of the fourbuttons is pressed. This message displays the devicename and serial number.

C21

+5V

SCL

SCL

9 5

PIC16C923

RA1

U1

6

7

5

1

A0

A1

A2WP

SCL

GND

VCC2

3

6

4

U324C01

R3

RA0

SDA

+5V SDA SDA8

0.1F

4.7k

ButtonsControl Mode

1 2 3 4

X X X X Clear WHr, restore calibration values

X X Set Clock

X X CalibrationDS00220A-page 4 2000 Microchip Technology Inc.

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Normal OperationResults of the various calculations are displayed onthe LCD. Each result is displayed for two seconds withan update after one second. If no buttons are pressed,the next mode is displayed. Holding any button keepsthe display in the present mode, for as long as the but-ton is held. New results will be displayed each second(see Table 2). TABLE 2: DISPLAY MODES

TimeThe first result displayed is the time of day in the formHH:MM:SS. If the time of day was not set at RESET,this indicates the time since power-up (days are notrecorded).RMS VoltageThe RMS voltage is computed by reading the RMSvoltage value from the CS5460. This is a 24-bit valuewith a range of 0.000 to 1.000, representing a fractionof the full scale voltage. The 16 most significant bitsare multiplied by the full scale voltage (as 16-bits) toproduce the actual RMS voltage on the line, as a16-bit binary number. This is converted to a 5 digitpacked BCD number. The LCD display is blanked andE and the appropriate decimal point are displayed.The packed BCD number is then displayed, afterdetermining which digits (leading zeros) should remainblank.After one second, the value is updated and displayedagain. After another second, execution proceeds tothe next mode if no buttons were pressed. If a buttonwas pressed, the two-second counter that controlswhen the next subroutine should be executed iscleared, extending the time that the value is displayed.This code is repeated in all display subroutines.RMS CurrentThe RMS current is computed and displayed similar tothe RMS voltage. The only differences are the fullscale current is used, a C is displayed and a differentdecimal point is turned on. The button state is againchecked to see if execution should remain in this sub-routine.

Apparent PowerThe apparent power is computed in a subroutine(CalcAP), called by both the apparent power loop(APLoop) and the power factor loop (PFLoop). Theapparent power is computed by reading the RMS volt-age and RMS current from the CS5460, as before.The 16 most significant bits of each are multipliedtogether, giving a 32-bit result. The 16 most significantbits of the result are multiplied with the full scaleapparent power (16-bits) to get the actual apparentpower in volt amps in binary. The 16 most significantbits are returned for use by the calling subroutines.APLoop then converts the apparent power in binary(16-bits) to a 5-digit packed BCD number for display.The LCD display is blanked, AP is displayed andafter determining which digits should remain blanked(leading zeros), the apparent power is displayed. Thebuttons are again checked, as before, to determine ifexecution should remain in this subroutine.True PowerThe CS5460 was programmed to generate a pulsewhenever 10 WSec of energy has been transferred.For a 250W load, 25 pulses each second will be gen-erated. These pulses have been processed in an Inter-rupt Service Routine. When 360 pulses have beenaccumulated, 3600 WSec or 1 WHr has been trans-ferred. The total WHr is then incremented. The pulsecount is also recorded for each second.The apparent power is computed in a subroutine(CalcTP), called by both the true power loop(TPLoop) and the power factor loop (PFLoop). Cal-cTP multiplies the number of pulses received duringthe last second by 10 to compute the true power con-sumed by the load. The result is returned as the truepower in watts as a 16-bit binary number.TPLoop converts and displays the true power in thesame way as APLoop displays apparent power. Theonly difference is that TP is displayed instead ofAP. The buttons are again checked as before todetermine if execution should remain in this subrou-tine.Power Factor (PF)The power factor is computed by calling the CalcAPsubroutine to get apparent power in volt amps andthe CalcTP subroutine to get true power in watts. Thetrue power is divided by the apparent power to get thepower factor as a binary result, in the range of 0.000 to1.000. The binary power factor is multiplied by 1000and converted to a BCD number for display. Theappropriate decimal point is turned on.The buttons are checked as before to determine ifexecution should remain in the power factorsubroutine.

Display Value Displayed

HH:MM:SS Time

E RMS Voltage

C RMS Current

AP Apparent Power

TP True Power

PF Power Factor

Hr Total WHr 2000 Microchip Technology Inc. DS00220A-page 5

AN220

If apparent power is equal to 0, there is no load(IRMS = 0). This can result in a division by zero condi-tion. If a division by zero is detected, a PF of 1.000 isreported.The calculated power factor can also greatly exceed1.0. When this occurs, the power factor is reported asbeing 1.000. This occurs when the load characteristicsare rapidly changing (as when a motor is starting). Allthe measurements are not taken at exactly the sametime and the RMS values are calculated over a onesecond period. When the load reaches a steady statecondition, the power factor will again be correct.Energy (Watt-Hours)The WHLoop simply displays the WHr counter value.The binary count is converted to BCD. The BCD num-ber is then displayed with leading zeros blanked, usingthe same subroutine used by the apparent power andtrue power displays. The WHr counter is 16-bits long,allowing a maximum of 65,535 WHr to be displayed.When this count is exceeded, the count rolls over to 0.

Control ModesIf any of the three control modes was selected duringRESET, execution branches to one of these modulesto control how the Watt-Hour meter functions.When the control mode is terminated, a warm startRESET is executed.Calibrating the Watt-Hour MeterThe user is given the opportunity to adjust the calibra-tion constants. These constants will not be stored to the24C01. When reset, using the reset button, the calibra-tion values entered in the Calibrate mode will be usedfor making measurements and operation will resume asnormal, except that the new calibration values are used.If reset by removing power, or reset while pressing allfour buttons (clear total WHr), the constants stored inthe 24C01 will be used for operation.Enter Calibration mode by holding the two outer but-tons while pressing the reset button. The first threedigits display CAL, and the remaining digits indicatewhich constant is being adjusted. CAL EOFF will bedisplayed first. This indicates that the value displayedthe next time button 2 is pressed, will be the calibrationconstant for the voltage offset. Pressing button 2 againdisplays the constants value.The decimal point is next to the digit to be modified.Pressing button 3 will move the decimal point to thenext digit to the right. Pressing button 4 will incrementthat digit. Each digit will cycle from 0 to F, then back to0. Only that digit will be affected. Pressing button 1 atany time will cause the value for that constant to besent to the CS5460 and display the next constantname. See Table 3 for button functions.

TABLE 3: CALIBRATION MODE BUTTON FUNCTIONS

Table 4 shows the constant names and typical values.It is essential that the offsets be minimized before set-ting the gains.To set the offsets, remove AC power from theWatt-Hour meter and apply DC power of 8 to 12 VDCto C13. Adjust the offset constants for minimum RMSresults (there is a null in both the current and voltagechannels). Record the offsets.Apply AC power to the Watt-Hour meter and removethe DC power from C13. Applying power in this orderprevents a loss of power to the CS5460. If power islost, reenter the offset values before adjusting the gainvalues. Apply a known resistive load to the Watt-Hourmeter output. Adjust the voltage and current gain con-stants so the indicated RMS voltage and currentmatch the actual load voltage and current. Adjust thepulse rate gain so the indicated true power matchesthe actual load power. Record the gain constants.Resetting the device now uses the constants justfound. If the total Watt-Hours is cleared, the originalconstants will be restored.The software was designed for demonstration pur-poses; therefore, the calibration constants cannot bewritten to the serial EEPROM. If desired, the user canmodify the code to write the new calibration constantsto the EEPROM.

ButtonFunction

1 2 3 4

X Writes constant to CS5460 and displays next constant name

X Displays each constant name and its value in turn

X Selects next digit and moves decimal point

X Increments selected digitDS00220A-page 6 2000 Microchip Technology Inc.

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TABLE 4: CALIBRATION MODE INDICATIONS, CONSTANT AND TYPICAL VALUES

Clear Total Watt-HoursThis option causes the total WHr to be cleared fromthe 24C01 and RAM, and copies calibration datastored in the 24C01 back to the CS5460. The wordCLEAR is displayed until the buttons are released.Setting the Real Time ClockCL is displayed in the two digits at the left edge of thedisplay. The current time is displayed in the remainingsix digits.If buttons 2 and 4 are pressed together, the hours areincremented. If buttons 3 and 4 are pressed, the min-utes are incremented. If the minutes roll over from 59to 0, the hours will not be affected. If button 1 ispressed, CL is cleared from the display and execu-tion proceeds to the main loop. Pressing Button 2, 3,or 4 alone has no effect (see Table 5).TABLE 5: CLOCK SET MODE BUTTON

FUNCTIONS

POSSIBLE ENHANCEMENTSAn idea to simplify the calibration process is pre-sented, along with ideas for adding a battery backupand event logging.Power FactorAs reactive loads draw current out of phase with theline voltage, there is an associated phase angle. Thecosine of this angle provides the power factor.The power factor will never exceed 1.000. Resistiveloads will show a very high power factor, while reactiveloads, such as motors, will show lower power factors.Loads with great harmonic content (such as mostpower supplies) will also indicate a low power factor.Power Factor Correcting (PFC) loads will indicate veryhigh power factors.

CalibrationThe calibration process assumes the user has the timeand understanding to determine the calibration con-stants. This process can be greatly simplified. TheCS5460 has the capability of determining offsets andgains. By commanding the CS5460 to perform an off-set calibration, the offset constants can be found veryquickly. The calibration program would indicate themeasured value being calibrated and allow the user toadjust the constant, without actually having to knowwhat the constant was. When a satisfactory measure-ment is achieved, the constant would then be writtento the 24C01.The code presented in this application note almostcompletely fills the first code page of the PIC16C923.The second code page could be dedicated to a cali-bration program.Battery BackupSome users may wish to have the real time clock con-tinue to run, even during a loss of power. Thisbecomes possible by adding a backup battery topower the PIC16C923 and allow the Timer1 oscillatorto operate. This would be the time base for the realtime clock. The code to use Timer1 and its oscillatorhas been included. To extend the life of the battery, itwould power only the PIC16C923.Event LoggingThe 24C01 provides 128 bytes of non-volatileEEPROM memory. Currently, only 17 bytes are usedfor storing calibration data, total energy, and a deviceserial number. The remaining memory could be usedto record power line events, such as black-outs,brown-outs, surges and load peaks. With a real timeclock, the times of these events could also berecorded. Recording black-outs and brown-outs wouldrequire that the backup battery also power the 24C01.

Indication Constant Calibration Value(120V, 10A) CS5460 Default

EOFF Voltage Offset 0x00CCBB = +0.00624 0x000000 = 0.00000COFF Current Offset 0xFEB320 = -0.01015 0x000000 = 0.00000E GA Voltage Gain 0x2C2F62 = 0.69039 0x400000 = 1.00000C GA Current Gain 0x298610 = 0.64917 0x400000 = 1.00000P GA Pulse Rate Gain 0x01FEF2 = 510.95 0x0FA000 = 4000.000

ButtonFunction

1 2 3 4

X Done setting clock

X X Increment hours

X X Increment minutes 2000 Microchip Technology Inc. DS00220A-page 7

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APPENDIX A: EEPROM DATA MAP APPENDIX B: SOURCES

The LCD routines came from PICDEM-3TM. Adjust-ments may have been made to the segment and com-mon definitions to account for the use of a differentLCD panel than was used in PICDEM-3.The BIN2BCD routine is loosely based on theB2_BCD_Looped routine in BCD.ASM of applicationnote AN544. This function was originally written for thePIC17CXXX family, but it has been modified for thePIC16CXXX family.The multiply and divide math routines were copiedfrom application note AN617.The data sheet for the PIC16C923 can be found athttp://www.microchip.com. Search for DS30444E orPIC16C923.The data sheet for the 24C01 can be found athttp://www.microchip.com. Search for DS20071J or24C01.The data sheet for the CS5460 can be found athttp://www.crystal.com. Search for DS279PP3 orCS5460.

Address Description

0x00 Device Serial Number

0x01 Voltage Offset MSB

0x02 Voltage Offset

0x03 Voltage Offset LSB

0x04 Current Offset MSB

0x05 Current Offset

0x06 Current Offset LSB

0x07 Voltage Gain MSB

0x08 Voltage Gain

0x09 Voltage Gain LSB

0x0A Current Gain MSB

0x0B Current Gain

0x0C Current Gain LSB

0x0D Watt-Hour MSB

0x0E Watt-Hour LSB

0x0F Pulse Rate Gain MSB

0x10 Pulse Rate Gain

0x11 Pulse Rate Gain LSBDS00220A-page 8 2000 Microchip Technology Inc.

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APPENDIX C: SCHEMATICS

FIGURE C-1: PIC16C923 CONNECTIONS

32.768kHZ

Y1

33pF

C2C1

33pF .47F

C3 R1124k

12 RB113 RB014 RC315 RC416 RC517 C118 C219 VLCD220 VLCD321 AVDD22 VDD23 VSS24 OSC1

10 RA4

25 OSC226 RC0

59RG658RG557RG456RG355RG254RG153RG052RG751RF750RF649RF548RF447RF346RF245RF1

60RD5

44RF0

11 RA5

U116C923PLCC

CPUCLK

+5V

C5.47F

C6 .47FC7 .47FC8 .1F

SEG14SEG13SEG12

SEG19SEG18SEG17SEG16SEG15

SEG20

COM3

432

1S1

SCLK

SDOSDI

RB4RB5

RESET

COM2

SEG25SEG24SEG23SEG22SEG21

SEG26

+5V

RB7RB6

EOUT

R210k

C4

.1F

C10

.1F

+5V

COM1

8R

A27

VSS

6R

A15

RA0

4R

B23

RB3

2M

CLR

1N

C68

RB4

67R

B566

RB7

65R

B664

V DD

63CO

M0

62R

D7

9R

A3

61R

D6

29VL

CD1

30VL

CDAD

J31

RD

032

RD

133

RD

234

RD

335

RD

436

RE7

37R

E038

RE1

39R

E240

RE3

41R

E4

27R

C1

42R

E543

RE6

28R

C2

SEG

00SE

G01

SEG

02SE

G03

SEG

04

SEG

05SE

G06

SEG

07SE

G08

SEG

09SE

G10

SEG

11

EDIR

CSSDASCL

RESET

TOCS5460

TO CS5460

TO 24C01FROM BUTTONS

NC 2000 Microchip Technology Inc. DS00220A-page 9

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FIGURE C-2: LCD, 24C01, PUSH BUTTONS

432

1PB1

+5V

432

1

+5V

RB4 RB5 432

1

+5V

432

1

+5V

RB6 RB7

R1410k

R1510k

R1610k

R1710k

C17

.1F

C18

.1F

C19

.1F

C20

.1F

+5V

C11.1F

5SDA1A02A13A24 GND

7 WP

6 SCL

8 VCCU3

24C01

+5V

R34.7k

LCD DISPLAY

LCD1

SEG19

SEG21

SEG15

SEG13

SEG10

SEG07

SEG04

SEG01

SEG20SEG18SEG22SEG17SEG26SEG16SEG14SEG23SEG12SEG25SEG11SEG09SEG08SEG06SEG24SEG05SEG03SEG02SEG00

1

234

567

8

91011

1213

141516

17

181920

21

22

414039

383736

35

3433323130

292827

26252423

42COM3 COM3

COM2COM1

COM2COM18F, 8E

1B, 1CNC2B, 2C, 1DPNCNC3B, 3C, 2DPNCNC4B, 4C, 3DPNCNC5B, 5C, 4DPNCNC6B, 6C, 5DPNCNC7B, 7C, 6DPNC8B, 8C,7DP

8A, 8G, 8D7F, 7E

7A, 7G, 7D6L

6F, 6E6A, 6G, 6D

5F, 5E

5A, 5G, 5D4L

4F, 4E4A, 4G, 4D

3F, 3E

3A, 3G, 3D2L

2F, 2E2A, 2G, 2D

1F, 1E

1A, 1G, 1D

PB2 PB3 PB4

SDASCLDS00220A-page 10 2000 Microchip Technology Inc.

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FIGURE C-3: POWER SUPPLY, VOLTAGE SENSE, CURRENT SENSE

VIN

R18470

D4

3 IN 1OUT

U4LM7805-TO92

C13

1000F

T2

TRANS-2102

R8

VIN+

VIN-

C12

.1F

D21N914

D1

1N914

1 L2 G3 N

J2

IEC_F

R21

56, 1/2 W

T11J8

1J7

1J6

1L2G3N

J1

IEC_M1 J3

1 J4

1 J5 12 GA Wire

IIN+

GND2

+5 VREG

MOV

LOADSOURCE 2000 Microchip Technology Inc. DS00220A-page 11

AN220

FIGURE C-4: CS5460 CONNECTIONS

R11

1 k

R910k

IIN+VIN-

180k

R20 R12

100k(1)

VIN+100k(1)

R10

+5V

CPUCLK301

R25.01F

C24C25

.01F

10

R6

C16

.1F

R2610k

SCLK

CSSDOSDI

Y2

4.096MHz

EOUT

9 VIN+

12 VREFIN11 VREFOUT

13

VA-

4

DGND

21EOUT

22EDIR

20INT

5SCLK

6SDO

23SDI

7CS

19RESET

24XIN

1XOUT

2CPUCLK

17PFMON

3VD+

14VA+

15 IIN-

10 VIN-16 IIN+

U2

CS5460

RA4

+5V301R22

R23 301

C15

4700pF

R1910k

C9

.1F

C21

.1F

C14

0.015F

R2410k

+5 VREG

EDIR

VIN

Note: R10 and R12 are 121 kOhms for 220V Watt-Hour meters.DS00220A-page 12 2000 Microchip Technology Inc.

AN220

APPENDIX D: BILL OF MATERIALS

Cnt Component Name RefDes Description Digikey2 1N4001 D1-2 IN4001DICT-ND1 16C923PLCC U1 PIC16C924 (Microchip)1 SOCKET U1 A2144-ND1 24C01_TSOP U3 24CO1-BC (Microchip)2 CAP150 C1-2 33pF Capacitor P4843-ND12 CAP0805 C4, C8-12,

C16-21.1F Capacitor PCC1864CT-ND

2 CAP1206 C24-25 .01F Capacitor PCC103BCT-ND4 CAP1206 C3, C5-7 .47F Capacitor PCC1891CT-ND1 CAP1206 C15 4700pF Capacitor PCC472BCT-ND1 CAP1206 C14 15000pF Capacitor PCC153BCT-ND1 CAP-RAD400D C13 1000F Capacitor P5142-ND1 CRYSTAL Y2 4.096MHz Crystal X082-ND1 CRYSTAL_32KHZ Y1 32kHz Crystal SE3201-ND1 CS5460 U2 CS4560 (Crystal Semiconductor)1 CSE187-L T1 Current Transformer 10515-ND1 IEC_F J2 Socket 509-1271 (Allied)1 IEC_M J1 Plug 509-1269 (Allied)1 LCD_VIM-808-DP LCD1 VIM-808-DP-RC-S-HV 153-1057-ND1 LED_SMT D4 LED, Green LT1120CT-ND1 LM7805-TO92 U4 Voltage Regulator NJM78L05A-ND1 MOV R8 MOV P7259-ND1 RES600 R21 56 1/2W Resistor 56H-ND1 RES1206 R11 1k Resistor P1.0KECT-ND1 RES1206 R3 4.7k Resistor P4.7KECT-ND1 RES1206 R6 10 Resistor P10ECT-ND9 RES1206 R2, R9,

R14-17, R19, R24, R26

10k Resistor P10KECT-ND

1 RES1206 R1 124k Resistor P124KFCT-ND1 RES1206 R20 121k Resistor P121KFCT-ND3 RES1206 R22-23, R25 301 Resistor P300ECT-ND1 RES1206 R18 470 Resistor P470ECT-ND2 RES1206 R10, R12 100k Resistor P100KECT-ND5 SW-B3F1000 S1, PB1-4 SW404-ND5 KEY CAP S1, PB1-4 SW450-ND1 TRANS-2102 T2 Transformer 12 VAC/0.09 A MT2113-ND1 Plastic case 141840 (Jameco)1 Printed Circuit BoardMisc:4 4-40 X 3/8 machine screw for J1, J24 4-40 hex nut2 ft 12 ga stranded copper wire1 20-pin machined pin IC socket to cut up for pin extensions for S1-S5 2000 Microchip Technology Inc. DS00220A-page 13

AN220APP

END

IX E

:SO

URCE

CO

DE

MPASM 02

.30.

11 Intermedi

ate

WAT

T_MT

R.AS

M

5-25

-200

0 1

3:31

:13 PAGE 1

LOC OBJECT CODE LINE SOURCE TEXT

VALUE

00

001

l

ist

st

=off

;

sup

pres

s li

st f

ile

symb

ol t

able

00

002

l

ist

n=

0 ; suppress li

st f

ile

page

bre

aks

00

003

00

004

;***

****

****

****

****

****

****

****

************************************

00

005

; Co

nfig

urat

ion

swit

ches

. Th

ese

control

what

cod

e is

ass

embl

ed.

00

006

00

007

;

Sele

ct t

he d

esir

ed o

pera

ting

volta

ge b

y co

mmen

ting

out

all

but

00

008

;

the

desi

red

volt

age

rang

e 00

009

#

defi

ne

VO

LT120

;

120

V no

mina

l fu

ll s

cale

ran

ge 00

010

;

#

defi

ne

VO

LT220

;

220

V no

mina

l fu

ll s

cale

ran

ge 00

011

00

012

;

Sele

cts

the

real

tim

e cl

ock

frequency source,

00

013

;

#

defi

ne

TM

R1OSC ; de

fine

d if

usi

ng 3

2kHz

T1O

SC,

comm

ent out if

ano

ther

RTC source

00

014

00

015

;***

****

****

****

****

****

****

****

*****************************

00

016

; So

ftwa

re L

icen

se A

gree

ment

00

017

; 00

018

; Th

e so

ftwa

re s

uppl

ied

here

with

by Mic

roch

ip T

echn

olog

y In

corp

orat

ed (

the

00

019

; "C

ompa

ny")

for

its

PIC

micr

o M

icrocontroll

er i

s in

tend

ed a

nd s

uppl

ied

to

Softw

are

Lice

nse

A

gree

men

tTh

e so

ftwa

re s

upp

lied

here

with

by

Mic

roch

ip T

ech

nolo

gy I

nco

rpor

ate

d (th

e Co

mpa

ny) f

or

its P

ICm

icro

M

icro

con

trolle

r is

inte

nde

d an

d su

pplie

d to

yo

u, th

e C

ompa

nys

cu

sto

me

r, fo

r u

se s

ole

ly an

d e

xclu

sive

ly on

Mic

roch

ip P

ICm

icro

M

icro

con

trolle

r pro

d-u

cts.

The

softw

are

is o

wn

ed

by th

e C

om

pany

a

nd/

or

its su

pplie

r, a

nd

is pr

ote

cte

d un

der a

pplic

abl

e c

opy

right

la

ws.

Al

l rig

hts

are

re

serv

ed.

Any

use

in vi

olat

ion

of t

he fo

rego

ing

rest

rictio

ns m

ay

subje

ct th

e u

ser

to cr

imin

al s

anct

ion

s u

nde

r app

lica

ble

law

s, a

s w

ell a

s to

ci

vil

liabi

lity fo

r th

e br

each

of t

he te

rms

an

d co

ndi

tion

s o

f thi

s lic

ense

.

THIS

SO

FTW

ARE

IS PR

OVI

DED

IN A

N A

S IS

CO

NDIT

ION.

NO

WAR

RAN

TIES

, W

HET

HER

EXP

RES

S, IM

PLIE

D O

R ST

ATU-

TORY

, IN

CLUD

ING

, BUT

N

OT

LIM

ITED

TO

, IM

PLIE

D W

ARR

ANTI

ES O

F M

ERCH

ANTA

BILI

TY AN

D F

ITN

ESS

FOR

A PA

RTIC

U-LA

R P

UR

POSE

AP

PLY

TO TH

IS SO

FTW

ARE.

TH

E CO

MPA

NY

SHAL

L N

OT,

IN

AN

Y CI

RCUM

STAN

CES,

BE

LI

ABLE

FO

RSP

ECIA

L, IN

CID

ENTA

L O

R CO

NSEQ

UEN

TIAL

DAM

AGES

, FO

R AN

Y R

EASO

N W

HAT

SOEV

ER.DS00220A-page 14 2000 Microchip Technology Inc.

AN220 00

020

; yo

u, t

he C

ompa

nys customer, fo

r us

e so

lely

and

excl

usiv

ely

on M

icro

chip

00

021

; PI

Cmic

ro M

icro

cont

roll

er p

rodu

cts.

00

022

; 00

023

; Th

e so

ftwa

re i

s ow

ned

by t

he C

ompa

ny a

nd/o

r its suppli

er,

and

is p

rote

cted

00

024

; un

der

appl

icab

le c

opyr

ight

law

s. A

ll r

ight

s are reserved.

Any

use

in

00

025

; vi

olat

ion

of t

he f

oreg

oing

res

tric

tion

s ma

y subj

ect

the

user

to

crim

inal

00

026

; sa

ncti

ons

unde

r ap

plic

able

law

s, a

s we

ll a

s to civ

il l

iabi

lity

for

the

00

027

; br

each

of

the

term

s an

d co

ndit

ions

of

this

license.

00

028

; 00

029

; TH

IS S

OFTW

ARE

IS P

ROVI

DED

IN A

N "A

S IS

" CO

NDITION. NO WARRANTIES, WHETHER

00

030

; EX

PRES

S, I

MPLI

ED O

R ST

ATUT

ORY,

INC

LUDI

NG,

BUT NOT LIMITED TO, IMPLIED

00

031

; WA

RRAN

TIES

OF

MERC

HANT

ABIL

ITY

AND

FITN

ESS

FOR A PARTICULAR PURPOSE APPLY

00

032

; TO

THI

S SO

FTWA

RE.

THE

COMP

ANY

SHAL

L NO

T, I

N ANY CIRCUMSTANCES, BE LIABLE

00

033

; FO

R SP

ECIA

L, I

NCID

ENTA

L OR

CON

SEQU

ENTI

AL D

AMAGES, FOR ANY REASON WHATSOEVER.

00

034

00

035

00

036

;***

****

****

****

****

****

****

****

****

****

****

*****************

00

037

; Au

thor

: St

ephe

n Hu

mber

d, B

rett

Dua

ne 00

038

; Co

mpan

y: M

icro

chip

Tec

hnol

ogy

Inc.

00

039

; Re

visi

on:

1.1

00

040

; Da

te:

5-15

-200

0 00

041

; As

semb

led

usin

g MP

LAB

4.99

.07,

MPA

SM 2

.30.

11 00

042

;***

****

****

****

****

****

****

****

****

****

****

*****************

00

043

; In

clud

e Fi

les:

CAL

.INC

ca

libr

atio

n co

nstants

00

044

;

PR3

.INC

LC

D se

gmen

t de

finiti

ons

00

045

;

P16

C924

.INC

St

anda

rd M

icro

chip in

clud

e fi

le f

or P

IC16

C923

/924

00

046

;***

****

****

****

****

****

****

****

****

****

****

*****************

00

047

; Th

is p

rogr

am c

ontr

ols

and

read

s da

ta f

rom

The Crystal

CS45

60 00

048

; Si

ngle

Pha

se B

i-Di

rect

iona

l Po

wer/

Ener

gy I

C 00

049

; an

d di

spla

ys i

t on

a e

ight

dig

it L

CD u

sing

the LCD dr

ive

00

050

; fu

ncti

on o

f a

PIC1

6C92

3. 00

051

00

052

; Th

e CS

5460

mea

sure

s li

ne v

olta

ge a

nd c

urre

nt transfe

red

betw

een

00

053

; th

e li

ne (

sour

ce)

and

the

load

. Th

e in

stan

taniou

s vo

ltag

e an

d cu

rren

t 00

054

; me

asur

emen

ts a

re u

sed

to c

ompu

te (

with

in t

he CS54

60)

inst

anta

niou

s po

wer,

00

055

; RM

S vo

ltag

e, R

MS c

urre

nt,

and

accu

mula

ted

energy. All

of

thes

e 00

056

; me

asur

emen

ts a

nd c

alcu

lati

on r

esul

ts a

re a

valibl

e to

the

PIC

16C9

23 v

ia S

PI.

00

057

; 00

058

; Th

e RM

S vo

ltag

e an

d RM

S cu

rren

t ar

e di

spla

yed and

used

to

calc

ulat

e ap

aren

t 00

059

; po

wer.

00

060

; 00

061

; A

puls

e ou

tput

(EO

UT)

on t

he C

S546

0 in

dica

tes whe

n a

prog

rama

ble

amou

t of

00

062

; en

ergy

has

bee

n tr

ansf

erre

d be

twee

n th

e li

ne and

the

load

. An

othe

r ou

tput

00

063

; (E

DIR)

ind

icat

es t

he d

irec

tion

of

that

tra

nsfer (i

f a

load

is

high

ly 00

064

; re

acti

ve,

eneg

ry f

lows

fro

m th

e lo

ad t

o th

e line

). T

hese

pul

ses

are

coun

ted

00

065

; by

the

PIC

16C9

23 t

o me

asur

e an

d di

spla

y to

tal energy transfe

rred

in

Watt

Hour

s 2000 Microchip Technology Inc. DS00220A-page 15

AN220

00

066

; 00

067

; Tr

ue p

ower

is

meas

ured

by

coun

ting puls

es f

or 1

sec

ond.

The

CS5

460

has

been

00

068

; pr

ogra

mmed

to

gene

rate

a p

ulse

for each

10Wa

ttSe

cond

s of

ene

rgy

tran

ferr

ed.

00

069

; Th

e pu

lse

coun

t is

mul

tipl

ied

by 10

to c

alcu

late

tru

e po

wer.

00

070

; 00

071

; Ap

aren

t po

wer

and

true

pow

er a

re dis

play

ed,

and

are

used

to

calc

ulat

e th

e 00

072

; po

wer

fact

or o

f th

e lo

ad.

00

073

; 00

074

; Th

e CS

4560

out

puts

a 4

.096

MHz

clock

for

use

by t

he P

IC16

C923

as

the

syst

em 00

075

; cl

ock.

Thi

s co

de o

ffer

s th

e op

tion of

usin

g th

is s

ourc

e as

the

rea

l ti

me c

lock

00

076

; so

urce

wit

h CC

P1 i

n co

mpar

e/in

terrupt only

/spe

cial

eve

nt m

ode,

or

usin

g th

e Ti

mer1

00

077

; os

cill

ator

wit

h a

32.7

68KH

z cr

ystal.

The

har

dwar

e pr

ovid

ed o

n th

e de

mo u

nits

00

078

; su

ppor

ts b

oth

opti

ons.

00

079

; 00

080

; Ev

ery

8 mi

nute

s, t

he c

urre

nt a

ccumula

ted

ener

gy (

WHr)

is

writ

ten

to t

he 2

4C01

00

081

; se

rial

EEP

ROM.

Thi

s sa

ves

the

total

ener

gy d

urin

g ti

mes

when

the

AC

powe

r is

rem

oved.

00

082

; 00

083

; Ca

libr

atio

n co

nsta

nts

are

also

stored

in t

he 2

4C01

. Th

ese

are

read

fro

m th

e 24

C01

00

084

; an

d wr

itte

n ba

ck t

o th

e CS

5460

when power is

rea

ppli

ed,

and

when

the

tot

al e

negy

is

00

085

; cl

eare

d fr

om t

he 2

4C01

. Th

e co

de to read

the

cons

tant

s fr

om c

al.i

nc a

nd w

rite

the

m to

00

086

; th

e 24

C01

has

been

inc

lude

d, b

ut has

bee

n co

mmen

ted

out.

00

087

; 00

088

; On

res

et,

the

PIC1

6C92

3 ch

ecks

the 4

cont

rol

butt

ons

for

3 sp

ecif

ic s

tate

s. O

ne s

tate

00

089

; al

lows

the

use

r to

set

the

tim

e of the

rea

l ti

me c

lock

. An

othe

r st

ate

clea

rs t

he 00

090

; to

tal

WHr

for

the

24C0

1 an

d re

writes the

cal

ibra

tion

con

stan

ts t

o th

e CS

5460

. A

00

091

; th

ird

stat

e al

lows

the

use

r to

adjus

t th

e ca

libr

atio

n co

nsta

nts

in t

he C

S546

0. 00

092

; 00

093

; Wr

itte

n by

Ste

phen

Hum

berd

, Mi

crochi

p Te

chno

logy

10/

08/1

999

00

094

;***

****

****

****

****

****

****

****

*****************************

00

095

; Op

tion

al R

eal

Time

Clo

ck s

ourc

es (T1

OSC

or C

S546

0 CP

UCLK

out

put)

00

096

; Mo

nito

r CS

5460

!ED

IR o

utpu

t. 00

097

; Ch

ange

Pul

se R

ate

from

128

pul

ses/KW

Hr (

1 pu

lse/

28,1

25Ws

ec)

00

098

;

to

1 pu

lse/

10Ws

ec (

100W

loa

d generates 10

pul

ses

per

seco

nd)

00

099

; Us

e 16

-bit

s of

CS5

460

data

rat

her tha

n 24

-bit

s 00

100

;

(CS

5460

set

ting

s ar

e st

ill

24-bit

s lo

ng)

00

101

; Ad

ded

Appa

rent

Pow

er,

True

Pow

er, and

Powe

r Fa

ctor

Fun

ctio

ns.

00

102

; Mo

ved

Puls

e Ra

te r

egis

ter

valu

e to EEPROM.

00

103

; Mo

difi

ed C

alib

rate

rou

tine

to

includ

e Pu

lse

Rate

"Ga

in"

func

tion

. 00

104

; Ge

nera

l co

de s

ize

redu

ctio

n. (

Fits in

PIC

16C9

23.)

00

105

; 00

106

; If

the

CPU

CLK

outp

ut o

f th

e CS

5460 i

s 4.

096M

Hz,

the

CCP1

mod

ule

00

107

; ca

n be

use

d (a

s is

) fo

r th

e re

al tim

e cl

ock

refe

renc

e in

stea

d of

the

00

108

; Ti

mer1

Osc

illa

tor.

If

the

CPUC

LK output is

som

e ot

her

freq

uenc

y, 00

109

; CC

PR1H

:CCP

R1L

will

nee

d to

be

adjusted

to m

ake

CCP1

gen

erat

e an

int

erru

pt 00

110

; ev

ery

0.5

seco

nd.

00

111

;DS00220A-page 16 2000 Microchip Technology Inc.

AN220 00

112

; If

the

Tim

er1

osci

llat

or i

s to

be

used

as

the Real

Time

Clo

ck b

ase,

00

113

; un

comm

ent

line

46

("#d

efin

e TM

R1OS

C").

Thi

s causes CCP1

code

to

00

114

; be

dis

able

d an

d T1

OSC

code

to

be e

nabl

ed.

00

115

; 00

116

; Mo

difi

ed b

y Br

ett

Duan

e, M

icro

chip

Tec

hnol

ogy 5/

25/2

000

00

117

;***

****

****

****

****

****

****

****

****

****

****

*****************

00

118

00

119

l

ist

p=16

c924

00

120

#

incl

ude

00

001

LIST

00

002

; P1

6C92

4.IN

C S

tand

ard

Head

er F

ile,

Ver

sion

1.01

M

icro

chip

Tec

hnol

ogy,

Inc

. 00

289

LIST

2007

3

FF1

00

121

_

_CON

FIG

_CP_

OFF&

_WDT

_OFF

&_XT

_OSC&_PWRTE_ON

00

122

00

123

e

rror

leve

l

-3

02

; suppress assembl

er w

arni

ng m

essa

ge "

Oper

and

not

in ba

nk

0" 00

124

e

rror

leve

l

-3

06

; suppress assembl

er w

arni

ng m

essa

ge "

Cros

sing

pag

e bo

unda

ry"

00

125

00

126

00

127

;***

****

****

****

****

****

****

****

****

****

****

************************

00

128

; va

riou

s eq

uate

s 00

129

00

130

; Mi

croc

hip

MATH

lib

rary

AN6

17 00

0000

07

00

131

MSB

e

qu

7

00

0000

00

00

132

LSB

e

qu

0

00

133

00

134

; CS

5460

var

iabl

es (

stri

ng e

quat

es)

00

0000

FE

00

135

SYNC

0

e

qu

0x

FE

; Sync by

tes

sent

as

dumm

y da

ta d

urin

g re

ads

00

0000

FF

00

136

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1

e

qu

0x

FF

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n 3

SYNC

1 by

tes

at a

tim

e. 00

137

00

138

#

IFND

EF

TM

R1OS

C 00

0000

7F

00

139

CCPC

OUNT

e

qu

0x

7F

; Varia

ble

in s

hare

d RA

M. C

CP1

inte

rrup

t co

unte

r, 00

140

E

NDIF

; not used

with

Tim

er1

osci

llat

or.

00

141

00

142

;***

****

****

****

****

****

****

****

****

****

****

************************

00

143

; Va

riab

les

in R

AM 00

144

c

bloc

k

0x

20

; Load

vari

able

s in

to R

AM s

tart

ing

at 0

x20

00

0000

20

00

145

TEMP

A

;

scr

atch

pad

00

0000

21

00

146

TEMP

B

;

scr

atch

pad

00

147

00

0000

22

00

148

SECO

ND

;

TIM

E va

riab

les

00

0000

23

00

149

MINU

TE

;

TIM

E va

riab

les

00

0000

24

00

150

HOUR

;

TIM

E va

riab

les

00

151

00

0000

25

00

152

WATT

TMPH

;

ene

rgy

puls

e co

unte

r MS

B 00

0000

26

00

153

WATT

TMPL

;

ene

rgy

puls

e co

unte

r LS

B 00

0000

27

00

154

WATT

HRH

;

Acc

umul

ated

WHr

MSB 2000 Microchip Technology Inc. DS00220A-page 17

AN220

00

0000

28

00

155

WATT

HRL

;

Acc

umul

ated

WHr

LSB

00

156

00

0000

29

00

157

PULS

ECH

;

"Pu

lses

per

sec

ond" counter MSB

00

0000

2A

00

158

PULS

ECL

;

"Pu

lses

per

sec

ond" counter LSB

00

159

00

0000

2B

00

160

PULD

ISPH

;

"Pu

lses

dur

ing

previo

us s

econ

d" M

SB 00

0000

2C

00

161

PULD

ISPL

;

"Pu

lses

dur

ing

previo

us s

econ

d" L

SB 00

162

00

0000

2D

00

163

APH

;

App

aren

t Po

wer

MSB (1

6 bi

t) (

Volt

Amps

in

bina

ry)

00

0000

2E

00

164

APL

;

App

aren

t Po

wer

LSB

00

165

00

0000

2F

00

166

TPH

;

Tru

e Po

wer

MSB

(16 bi

t) (

Watt

s in

bin

ary)

00

0000

30

00

167

TPL

;

Tru

e Po

wer

LSB

00

168

00

0000

31

00

169

PFH

;

Pow

er F

acto

r MS

B (16

bit)

(un

itle

ss i

n bi

nary

) 00

0000

32

00

170

PFL

;

Pow

er F

acto

r LS

B 00

171

00

172

;Mor

e ge

nera

l va

riab

les

00

0000

33

00

173

POIN

TER

;

Poi

nts

to t

he c

haracters in

ini

tial

00

0000

34

00

174

PTRT

MP

;

scr

olli

ng m

essa

ge 00

0000

35

00

175

SERN

UM

;

uni

t se

rial

num

ber

00

0000

36

00

176

CALM

ODE

;

Cal

ibra

tion

Mod

e bein

g di

spla

yed

00

0000

37

00

177

CALD

IG

;

Cal

ibra

tion

dig

it bei

ng i

ncre

ment

ed 00

0000

38

00

178

UPDA

TEWH

;

Whe

n to

wri

te a

ccumula

ted

Watt

HOU

Rs t

o th

e EE

PROM

(ev

ery

8 mi

nute

s) 00

179

00

180

; SS

P va

riab

les

(SPI

mod

e) R

ecei

ve buf

fer

from

CS5

460

00

0000

39

00

181

RXDA

TA0

;

RXD

ATA

buff

er M

SB 00

0000

3A

00

182

RXDA

TA1

;

RXD

ATA

buff

er 00

0000

3B

00

183

RXDA

TA2

;

RXD

ATA

buff

er L

SB 00

184

00

185

; TX

DATA

buf

fer

(SPI

mod

e) T

rans

mit bu

ffer

to

CS54

60 00

0000

3C

00

186

TXDA

TA

;

com

mand

byt

e to

send

to t

he C

S456

0 00

0000

3D

00

187

TXDA

TA0

;

TXD

ATA

buff

er M

SB 00

0000

3E

00

188

TXDA

TA1

;

TXD

ATA

buff

er 00

0000

3F

00

189

TXDA

TA2

;

TXD

ATA

buff

er L

SB 00

190

00

191

; Mi

croc

hip

MATH

lib

rary

AN6

17 00

0000

40

00

192

AARG

B0

;

4 b

yte

argu

ment

and r

esul

t. B

0 is

alw

ays

MSB

00

0000

41

00

193

AARG

B1 00

0000

42

00

194

AARG

B2 00

0000

43

00

195

AARG

B3 00

0000

44

00

196

AARG

B4 00

197

00

0000

45

00

198

BARG

B0

;

2 b

yte

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ment

. B0 is

alw

ays

MSB

00

0000

46

00

199

BARG

B1 00

200 DS00220A-page 18 2000 Microchip Technology Inc.

AN220 00

0000

47

00

201

REMB

0

;

2 b

yte

rema

ider

(fr

om d

ivis

ion)

00

0000

48

00

202

REMB

1

;

B0

is a

lway

s MS

B 00

203

00

0000

49

00

204

TEMP

;

int

erna

l va

riab

les

00

0000

4A

00

205

TEMP

B0 00

0000

4B

00

206

TEMP

B1 00

0000

4C

00

207

TEMP

B2 00

0000

4D

00

208

LOOP

COUN

T 00

209

00

210

; 16

bit

bin

ary

to B

CD v

aria

bles

- S

ee a

pnot

e AN54

4 00

0000

4E

00

211

R0

; ou

tput

byt

es 1

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00

0000

4F

00

212

R1

;

1ks, 10

0s di

gits

00

0000

50

00

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R2

;

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s di

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00

214

00

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51

00

215

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L

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00

0000

52

00

216

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H 00

217

00

0000

53

00

218

COUN

T

;

int

erna

l va

riab

le 00

219

00

0000

54

00

220

BYTE

COUN

T

;

EEP

ROM

vari

able

s (f

irmw

are

I2C)

00

0000

55

00

221

EEAD

DR

;

EEP

ROM

addr

esse

s 00

0000

56

00

222

EEDA

TA

;

EEP

ROM

data

00

0000

57

00

223

EETE

MP 00

224

00

225

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erup

var

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0000

58

00

226

PWRU

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;

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st a

t po

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up to

00

0000

59

00

227

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;

see

if

warm

sta

rt o

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ld s

tart

00

228

00

0000

5A

00

229

LAST

RAM

;

dum

my m

arke

r (u

nuse

d) 00

230

00

231

e

ndc

00

232

00

233

c

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k

0x

70

; Load

vari

able

s in

to R

AM s

tart

ing

at 0

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00

234

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HARE

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in

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00

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00

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72

00

239

MODE

INC

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240

;

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t 0

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ery

odd

seco

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00

241

00

0000

73

00

242

UPDA

TE

;

Bit

0 s

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ach

seco

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243

00

0000

74

00

244

BUTT

ON

;

ind

icat

es b

utto

n pr

ess.

Bit

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tton

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pres

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00

0000

75

00

245

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ONTM

P

;

use

d on

ly i

n IS

R.

Bit

s

=1 =

but

tons

1-4

are

pre

ssed

00

246 2000 Microchip Technology Inc. DS00220A-page 19

AN220

00

247

; Sa

ve c

onte

xt b

efor

e in

terr

upt,

restore aft

er i

nter

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00

0000

76

00

248

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sav

e FS

R re

gist

er dur

ing

ISR

00

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77

00

249

TEMP

PCLA

TH

;

sav

e PC

LATH

reg

ister du

ring

ISR

00

0000

78

00

250

TEMP

W

;

sav

e W

regi

ster

durin

g IS

R 00

0000

79

00

251

TEMP

STAT

;

sav

e ST

ATUS

reg

ister du

ring

ISR

00

252

e

ndc

00

253

00

254

#

incl

ude

;

cal

ibra

tion

def

init

ions

00

001

; So

ftwa

re L

icen

se A

gree

ment

00

002

; 00

003

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e so

ftwa

re s

uppl

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here

with

by Mic

roch

ip T

echn

olog

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corp

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ed (

the

00

004

; "C

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PIC

micr

o Mic

rocontroll

er i

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tend

ed a

nd s

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005

; yo

u, t

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ompa

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r use sole

ly a

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xclu

sive

ly o

n Mi

croc

hip

00

006

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Cmic

ro M

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cont

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007

; 00

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and

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ecte

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s. All

rig

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are

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y us

e in

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olat

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of t

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trictio

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ay s

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ser

to c

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nal

00

011

; sa

ncti

ons

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law

s, as well

as

to c

ivil

lia

bili

ty f

or t

he 00

012

; br

each

of

the

term

s an

d co

ndit

ions of

this

lic

ense

. 00

013

; 00

014

; TH

IS S

OFTW

ARE

IS P

ROVI

DED

IN A

N "AS IS" CONDITION. NO WARRANTIES, WHETHER

00

015

; EX

PRES

S, I

MPLI

ED O

R ST

ATUT

ORY,

INCLUDING, BUT NOT LIMITED TO, IMPLIED

00

016

; WA

RRAN

TIES

OF

MERC

HANT

ABIL

ITY

AND FITNESS FOR A PARTICULAR PURPOSE APPLY

00

017

; TO

THI

S SO

FTWA

RE.

THE

COMP

ANY

SHALL NOT, IN ANY CIRCUMSTANCES, BE LIABLE

00

018

; FO

R SP

ECIA

L, I

NCID

ENTA

L OR

CON

SEQUENTIAL DAMAGES, FOR ANY REASON WHATSOEVER.

00

019

00

020

; **

****

****

**

DEFA

ULT

VALU

ES T

O WRITE TO EEPROM **************************

00

021

; Af

ter

the

cali

brat

ion

valu

es h

ave be

en d

eter

mine

d fo

r a

new

00

022

; un

it t

hose

val

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can

be l

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d into the

se "

#def

ines

" an

d 00

023

; wr

itte

n to

the

EEP

ROM

(see

Cal

ibratio

n in

stru

ctio

n do

cume

nt)

00

024

00

025

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S

ERNU

MBER

0x

01 ; Seria

l Nu

mber

00

026

00

027

#def

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V

OLTG

AINH

0x

29 ; volt

age

gain

MSB

00

028

#def

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V

OLTG

AINM

0x

66 ; volt

age

gain

00

029

#def

ine

V

OLTG

AINL

0x

6F ; volt

age

gain

LSB

00

030

00

031

#def

ine

C

URRG

AINH

0x

2A ; current gain

MSB

00

032

#def

ine

C

URRG

AINM

0x

2E ; current gain

00

033

#def

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C

URRG

AINL

0x

0A ; current gain

LSB

00

034

00

035

#def

ine

V

OLTO

FFH

0x

10 ; volt

age

offs

et M

SB 00

036

#def

ine

V

OLTO

FFM

0x

1A ; volt

age

offs

et 00

037

#def

ine

V

OLTO

FFL

0x

B6 ; volt

age

offs

et L

SB 00

038 DS00220A-page 20 2000 Microchip Technology Inc.

AN220 00

039

#def

ine

C

URRO

FFH

0x

FE

; current off

set

MSB

00

040

#def

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C

URRO

FFM

0x

DC

; current off

set

00

041

#def

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C

URRO

FFL

0x

16

; current off

set

LSB

00

042

00

043

#def

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P

ULSE

RATE

H

0x

02

; Puls

e ra

te "

gain

" MS

B 00

044

#def

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P

ULSE

RATE

M

0x

14

; Puls

e ra

te "

gain

" 00

045

#def

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P

ULSE

RATE

L

0x

CB

; Puls

e ra

te "

gain

" LS

B 00

046

00

047

; **

****

****

****

** F

ULL

SCAL

E VA

LUES

***

****

*******************************

00

048

; Th

e pr

esen

t re

v of

the

CS4

560

is n

ot l

inea

r over the

ent

ire

volt

age

rang

e 00

049

; Va

lues

use

d by

the

MAT

H ro

utin

es f

or c

oars

e cali

brat

ion

00

050

; ba

sed

on t

he v

alue

s we

cho

ose

for

the

volt

age di

vide

r 00

051

00

052

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M

AXCU

RRH

0x

00

; Full

sca

le c

urre

nt M

SB .

.. 2

5.0

Amps

00

053

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M

AXCU

RRL

0x

FA

; Full

sca

le c

urre

nt L

SB 00

054

00

055

#IFD

EF

V

OLT1

20

;

120V

nom

inal

full

scal

e 00

056

; fo

r 12

0V R

10 &

R12

= 1

00K,

R11

= 1

K 00

057

; us

e th

is v

alue

for

ful

l sc

ale

volt

age

00

058

00

059

#def

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M

AXVO

LTH

0x

00

; Full

sca

le v

olta

ge M

SB .

.. 2

37 V

OLTs

00

060

#def

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M

AXVO

LTL

0x

ED

; Full

sca

le v

olta

ge L

SB 00

061

00

062

#def

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M

AXPW

RH

0x

98

; Full

sca

le p

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MSB

...

237

V *

25.0

A =

5925

W 00

063

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M

AXPW

RL

0x

CE

; Full

sca

le p

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LSB

00

064

#END

IF 00

065

00

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EF

V

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20

;

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nom

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full

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e 00

067

; fo

r 22

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10 &

R12

= 1

21K,

R11

= 1

K 00

068

; us

e th

is v

alue

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ful

l sc

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age

00

069

00

070

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M

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0x

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; Full

sca

le v

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SB .

.. 2

82 V

OLTs

00

071

#def

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M

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LTL

0x

1A

; Full

sca

le v

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072

00

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0x

B3

; Full

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le p

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MSB

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282

V *

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W 00

074

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M

AXPW

RL

0x

F1

; Full

sca

le p

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LSB

00

075

#END

IF 00

076

00

077

00

078

00

255

#

incl

ude

; LCD, I2C

, an

d ma

th l

ibra

ry d

efin

itio

ns 00

001

;***

****

****

****

****

****

****

****

****

****

****

*****************

00

002

; So

ftwa

re L

icen

se A

gree

ment

00

003

; 00

004

; Th

e so

ftwa

re s

uppl

ied

here

with

by

Micr

ochi

p Techn

olog

y In

corp

orat

ed (

the

00

005

; "C

ompa

ny")

for

its

PIC

micr

o Mic

roco

ntro

ller

is

inte

nded

and

sup

plie

d to 2000 Microchip Technology Inc. DS00220A-page 21

AN220

00

006

; yo

u, t

he C

ompa

nys customer, fo

r use sole

ly a

nd e

xclu

sive

ly o

n Mi

croc

hip

00

007

; PI

Cmic

ro M

icro

cont

roll

er p

rodu

cts.

00

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00

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#