I2C optional label question

[aratti]

by the way, have you an idea about the Optionnal Label on I2C command
is it a GOTO or a GOSUB for you ?

As I told you in post#2 is a GOTO comand.

You can put a flag=0 before the I2Cread or I2Cwrite and use the label to direct to a TimeOut label, where you change Flag=1. In this way you will know if you had a timeout problem and discard the reading or writing and redo the process.

Al.

[Melanie]

Are you aware that the ADDRESS and the CONTROL should be a variable and NOT a constant? Leave bit 0 clear of the CONTROL byte... the I2C routines will use it internally.

[F1CHF]

Hi Melanie, still on board, super ! and working on Sunday time !
Aratti .. sorry, I didn't see the word GOTO ...thanks ..
It is clear for me, that the control and address parameters are confusing for me ...
I understand from the example, this is used with Eprom familly
Control parameter is the main address
and
address parametre is used to point to the address location in the Eprom !

I use for long time I2C commands in the simple way like
I2CWRITE DataPin,ClockPin,Control,{Address,}[Value{,Value...}]{,Label}

example :

datapin var PORTA.1
clockpin var PORTA.2
Main:
I2CWRITE datapin,clockpin,$C2,[11,22,33,44],errorI2C
etc ...
etc ...

errorI2C:
flash a led ....
goto Main

As I do not understand Control and address story, I always use this and It works
with a lot of synthetisers (SP5055 familly)
Now I decided to be more serious ! and check the frequency lock flag
(bit 6 of the SP 5055 register)
that why I try to READ like that
flag var byte
I2CREAD datapin,clockpin,$C3, [flag], errorI2C
if flag.6 = 1 then continue
else
goto main
endif

continue:
etc ...
etc ...

nb: $C2 or $C3 I am not sure, but I can check the good value ..

thanks for your help

[Melanie]

You did not understand my post... don't use CONSTANTS but use VARIABLES with I2C commands....

ControlByte var BYTE

.. ..

ControlByte=$C2
I2CREAD datapin,clockpin,ControlByte, [flag], errorI2C

[F1CHF]

Hello Melanie, morning ..
Oupps ...I will trust you as usual
I will test it today
thanks

[F1CHF]

I got it !
it works ..
my error was the missing brackets on the I2CREAD command
it seems that without the bracket the I2CREAD become a I2CWRITE !

I try using address $C2 or using a constant ... same results
thanks to everybody
francois

here is my HUGE code !
'*******************************************
'* Name : TX2300 avec 16F84 *
' Variable Definitions
SCL var PORTA.4
SDA var portA.3
LOCKBYTE var byte

Main:
I2CWRITE SDA,SCL,$C2,[$48,$F8,$AE,$FF],errorload
LOCK:
pause 100
I2CREAD SDA,SCL,$C2,[lockbyte]
Lcdout $FE, 1 ' Clear LCD screen
pause 50
lcdout "lock=", #lockbyte, " bit=", #lockbyte.6
pause 1000
goto lock

errorload:
Lcdout $FE, 1 ' Clear LCD screen
pause 50
lcdout "error load "
pause 1000
goto main