I2c & Variable Size

[Bill Legge]

SkiMask - thanks for your speedy reply. The code is below. The problem variable is
called 'LoopCounter' and is set at WORD length. THe loop does not increment.

If LoopCounter is made a BYTE all works as it should. Help?

'File...... Test Program
'
' Philips PCF8583 I2C RTC gives the time/date
' PIC16F877A on Mikro board is run @ 20 MHz
' After amendment to pbppic14.lib - now works at 20 MHz
'
' PIC LCD RS232 RTC DS1820 EEPROM
' --- --- ----- --- ------ ------
' C3 SCL ' I2C device, TRC clock
' C4 SDA ' I2C device, RTC data
' D2 RS ' LCD reset
' D3 EBIT ' LCD enable
' D4 DB4 ' LCD data 4
' D5 DB5 ' LCD data 5
' D6 DB6 ' LCD data 6
' D7 DB7 ' LCD data 7
'
' ----[ Variables ]---------------------------------------------------
'
DataPin var PORTC.4 ' RTC data
ClockPin var PORTC.3 ' RTC clock
Mins var byte ' Minutes on RTC
Hours var byte ' Hours on RTC
Days var byte ' Days on TTC
Months var byte ' Months on RTC
Time var byte[3] ' Holds months,days,hours,mins read from RTC
Dtime var byte[3] ' Holds months,days,hours,mins in HEX format
Units var byte ' Derived from Time
Tens var byte ' Derived form Time
CControl var byte ' Control byte for RTC
'
LoopCounter var word ' The 'problem' loop counter
J var byte ' Loop counter for RTC read/write
'
' ----[ Includes / Defines ]------------------------------------------
'
define OSC 20 'Now works at 20 MHz
DEFINE LCD_DREG PORTD 'Define PIC port used for LCD Data lines
DEFINE LCD_DBIT 4 'Define first pin of portb connected to LCD DB4
DEFINE LCD_RSREG PORTD 'Define PIC port used for RS line of LCD
DEFINE LCD_RSBIT 2 'Define Portb pin used for RS connection
DEFINE LCD_EREG PORTD 'Define PIC prot used for E line of LCD
DEFINE LCD_EBIT 3 'Define PortB pin used for E connection
DEFINE LCD_BITS 4 'Define the 4 bit communication mode to LCD
DEFINE LCD_LINES 2 'Define using a 2 line LCD
DEFINE LCD_COMMANDUS 2000 'Define delay time between sending LCD commands
DEFINE LCD_DATAUS 50 'Define delay time between data
'
' -----[ Initialization ]--------------------------------------------------
'
LoopCounter = 0 'EEPROM address counter - when I get it working!!!
J = 0 'Time[x] loop counter
CControl = %10100000 'Control word for RTC
'
' -----[ Main Program ]----------------------------------------------------
Start:
lcdout $fe,1,"Test Program"
Pause 1000
lcdout $fe,1

' -----[ Set Time ]-------------------------------------------------------
TimeSet
i2cwrite DataPin, ClockPin, CControl, $0, [%00001000]
'Control register for RTC, sets bit 3 to mask unwanted bits in time/date registers
i2cwrite DataPin, ClockPin, CControl, $2, [%00000000,%01011001,%00100011,%00110000,%00010001]
'BCD code, sets time registers to 0 Sec, 59 Min, 23 Hr, 30 Day, Month 11

' -----[ Main Program ]-----------------------------------------------------
Run:

' Time Read
i2cread DataPin, ClockPin, %10100000, $3, [Time[0], Time[1], Time[2], Time[3]]
Pause 20
'Time[0] = Min, Time[1] = Hr, Time[2] = Day, Time[3] = Month

' Time Show
for J = 0 to 3 'this works because the 'mask' is set and Time[x] bytes are all in BCD format.
Tens = Time[J] & %11110000
Tens = Tens>>4
Tens = Tens * 10
Units = Time[J] & %00001111
DTime[J] = Tens + Units 'Dtime is used to "Display Time"
next j

LCDout $FE, 1, "Mth: ", Dec DTime[3], " Day: ", dec DTime[2]
lcdout $FE, $C0, "Hrs: ", dec Dtime[1], " Min: ", DEC Dtime[0]
pause 1000

' Loop Counter
lcdout $FE,1,"Loop Ctr: ", DEC LoopCounter
pause 1000

LoopCounter = LoopCounter + 1

goto run

END


Sorry - the code has come out in a rather messy layout?

[skimask]

DEFINEs before everything else...that's my theory...ALL CAPs for all DEFINEs

DEFINE OSC 20 'Now works at 20 MHz

No COLON : after TimeSet

Don't use the ' or " in the comments after a line, except for the character defining the comment itself. When you get into mixing assembly with PBP, it'll mess you up in the future.

Maybe somebody else has some good ideas, 'cause I'm out at the moment...

[skimask]

Does this work? (I know it's not formatted like you had it, just see if it works)

DEFINE OSC 20               'Now works at 20 MHz
DEFINE LCD_DREG	PORTD	    'Define PIC port used for LCD Data lines
DEFINE LCD_DBIT	4		    'Define first pin of portb connected to LCD DB4
DEFINE LCD_RSREG PORTD	    'Define PIC port used for RS line of LCD
DEFINE LCD_RSBIT 2		    'Define Portb pin used for RS connection
DEFINE LCD_EREG	PORTD   	'Define PIC prot used for E line of LCD
DEFINE LCD_EBIT	3		    'Define PortB pin used for E connection
DEFINE LCD_BITS	4		    'Define the 4 bit communication mode to LCD
DEFINE LCD_LINES 2		    'Define using a 2 line LCD
DEFINE LCD_COMMANDUS 2000	'Define delay time between sending LCD commands
DEFINE LCD_DATAUS 50	    'Define delay time between data
sda var portc.4:scl var portc.3:min var byte:hour var byte:day var byte:month var byte
time var byte[3]:dtime var byte[3]:units var byte:tens var byte:control var byte
loopcounter var word:loopcnt1 var loopcounter.lowbyte:loopcnt2 var loopcounter.highbyte
j var byte:loopcnt1=0:loopcnt2=0:j=0:control=$a0
Start:     lcdout $fe,1,"Test Program":Pause 1000:i2cwrite sda,scl,control,0,[8]
i2cwrite sda,scl,control,2,[0,$59,$23,$30,$11]
run:     i2cread sda,scl,control,3,[Time[0],Time[1],Time[2],Time[3]]:Pause 20
for J=0 to 3:tens=((time[J] & $f0)>>4)*10:units=time[j] & $f:dtime[j]=tens+units:next j
lcdout $fe,1,"Mth: ",dec dtime[3]," Day: ",dec dtime[2]
lcdout $fe,$c0,"Hrs: ",dec dtime[1]," Min: ",dec dtime[0]:pause 1000
lcdout $fe,1,"Loop Ctr:",dec5 loopcounter:pause 1000   'might want to knock this down so the program runs a bit faster eh?
loopcnt1=loopcnt1+1:if loopcnt1 = 0 then loopcnt2=loopcnt2+1
goto run
END

(HCM strikes again!)