problem with i2c libary

boeseturbo · Joined: 23 Jul 2007 Posts: 65

Hi friends,

now I was sitting half day to get i2c slave libary to run Sad

((( I use 1281 as master (tried software i2c and hardware i2c) and attiny13 as slave device. Hardware is connected correct. 1281 can also read LM75 without any problems....

Here is my code for attiny13:

$regfile = "attiny13.dat"
$crystal = 9600000
'$baud = 57600

Config I2cslave = &H30
Config Adc = Single , Prescaler = Auto , Reference = Internal
Start Adc

Dim Choicer As Byte
Dim Wert_adc As Word
Dim Wert_byte As Word
Dim Wert_send As Byte

Do

If Choicer = 1 Then Wert_adc = Getadc(2)
If Choicer = 2 Then Wert_adc = Getadc(3)

Loop

I2c_master_needs_data:
_a1 = 100
Return

I2c_master_has_data:
Choicer = _a1
Return

master is:

$crystal = 16000000
$regfile = "M1281def.dat"
$baud = 4800
$hwstack = 600
$swstack = 600
$framesize = 600

$lib "i2c_twi.lbx"

Config Scl = Portd.0 ' we need to provide the SCL pin name
Config Sda = Portd.1 ' we need to provide the SDA pin name
Config Twi = 100000
I2cinit

do

I2cstart
I2cwbyte &H31
I2crbyte Test1 , Ack
I2cstop
waitms 20
loop

only "255" come back... so might be an error.... Have anybody an idea? I also tried software i2c on atmega1281... no luck Sad

Cheers

boeseturbo · Joined: 23 Jul 2007 Posts: 65

shit, bought wrong slave-cpu... should be tiny12 Sad

MAK3 · Joined: 24 Sep 2010 Posts: 449 Location: Germany

Duval JP · Joined: 22 Jun 2004 Posts: 1198 Location: France

hello,

I use attiny 45 for all small uses.
it is possible to use the registers as memory too but it is a big risk (see memory usage in the help)

for an I2C use, I think, you will need too much memory for the 12 or 13

bon courage
JP