I2C CONFUSION, Help needed please

[LinkMTech]

My bad, change the Read statement:

I2CREAD SDA,SCL,ADDR,[VALUE] ',Fail

[FromTheCockpit]

Still getting the same with the following code:

Value Var 	BYTE
Addr	Var	byte
Loc 	Var	Byte
'---------------------------------------------------------
Pause 500
	DEBUG "Start......",13,10
Value=0
Loc=0

Main:
High Led : Pause 500: Low Led : PAUSE 500
	Addr=$36
	I2CWRITE SDA,SCL,ADDR,[LOC],Fail1
	Addr=$37 : pause 10 ' Sometimes it is failing, leaving pause 10 makes it better.
	I2CREAD SDA,SCL,ADDR,[VALUE] ,Fail2
	PAUSE 25
	DEBUG  Value,13,10
	PAUSE 250
	DEBUG "Done....",13,10
WHILE 1 : WEND
Goto Main

Fail1:
while 1:	toggle portc.2 : pause 50 : wend 
goto main

Fail2:
WHILE 1
	High Portc.2 : Pause 250 : Low PortC.2 : Pause 250
WEND

[LinkMTech]

What if you assign the Read/Write addresses before hand?

Value Var 	BYTE
Addr	Var	byte
Loc 	Var	Byte

'---------------------------------------------------------
Pause 500
	DEBUG "Start......",13,10
Value=0
Loc=0
WR_Add CON $36
RD_Add CON $37

Main:
High Led : Pause 500: Low Led : PAUSE 500
	'Addr=$36
	I2CWRITE SDA,SCL,WR_Add,[LOC],Fail1
	'Addr=$37 : pause 10 ' Sometimes it is failing, leaving pause 10 makes it better.
	I2CREAD SDA,SCL,RD_Add,[VALUE] ,Fail2
	PAUSE 25
	DEBUG  Value,13,10
	PAUSE 250
	DEBUG "Done....",13,10
WHILE 1 : WEND
Goto Main

Fail1:
while 1:	toggle portc.2 : pause 50 : wend 
goto main

Fail2:
WHILE 1
	High Portc.2 : Pause 250 : Low PortC.2 : Pause 250
WEND

Question: Where is the "1" monitored at in these statements? Never seen it done this way before.

WHILE 1: WEND

[FromTheCockpit]

The manual says do not use constants for address.
Though I tried the above but the result is the same.

While 1 : Wend - I just put this just like that to halt the code.

[LinkMTech]

Oh yeah, no Constants.
Then give it to him straight!

Have you tried clearing the LOC and Value variables at the beginning of each loop just in case? Start with a clean slate every time.

Main:
    Loc=0
    Value=0
High Led : Pause 500: Low Led : PAUSE 500
    I2CWRITE SDA,SCL,$36,[LOC],Fail1
    I2CREAD SDA,SCL,$37,[VALUE] ,Fail2
    PAUSE 25
    DEBUG  Value,13,10
    PAUSE 250
    DEBUG "Done....",13,10
    
WHILE 1 : WEND
Goto Main

Fail1:
while 1:	toggle portc.2 : pause 50 : wend 
goto main

Fail2:
WHILE 1
	High Portc.2 : Pause 250 : Low PortC.2 : Pause 250
WEND

You're so close, I can smell it!
Or was that someone in the room?

[FromTheCockpit]

Did the above, no luck.
Doesn't like it straight, giving it $37/$36 direct sends it to Fail1 routine. So write statement fails.

Funny thing is that when it goes to Fail1, though there should be no output of data, IT does output some of the data. This looks like half the data compared to when cycle runs normally.

The code only run once and then I reset the PIC to run it again, so though it won't make any effect resetting the values in the main loop, I still tried with no luck. I am losing hairs on my head because of this now.

[LinkMTech]

Still Debugging after failing is strange. There is something else being introduced corrupting your instructions.

Use the Addr variables and see what happens when it free runs:

x VAR BYTE
RD_Addr = $37
WR_Addr = $36

Main:
High Led : Pause 500: Low Led : PAUSE 500
    I2CWRITE SDA,SCL,WR_Addr,[LOC],Fail1
    I2CREAD SDA,SCL,RD_Addr,[VALUE] ,Fail2
    PAUSE 25
    DEBUG  Value,13,10
    PAUSE 250
    DEBUG "Done....",13,10
    
WHILE 1 : WEND
Goto Main

Fail1:
FOR x = 0 TO 10
    toggle portc.2 : pause 50
NEXT x 
goto main

Fail2:
FOR x = 0 TO 10
	High Portc.2 : Pause 250 : Low PortC.2 : Pause 250
NEXT x
GOTO Main

Going to church now, BBL

[Demon]

Is that Write only an initialisation?

Shouldn't it be outside the Main loop?

Robert

[Demon]

This is a Touch IC. So shouldn't you check the device ID once, then check at another address within the loop to detect a touch? (not sure of trigger yet)

I'm dense, won't WHILE 1: WEND loop endlessly?

Robert

Edit: I see it now; 1 to 7 keys max for I2C, triggers lines out.

Also, looking in datasheet if it says 400kHz max. I think you might have to run fast.

4.1.1 max 400kHz, so you should be able to run slower.