i2c and the 18 project board

E

erdc

Member
Can you suceesfully use the i2c when there is the ULN2803A Darlington Array chip onboard? Or do you need to bypass this and get the signal right from the Picaxe pins?
 
B

BeanieBots

Moderator
You MUST make your I2C connections directly to the PICAXE and NOT after the ULN2803A Darlington Array. They will also need a 4k7 pull-up.
I2C is bi-directional which is why it is not possible to have any kind of driver chip between the PICAXE and the other device. Not to mention the fact that the ULN2803A Darlington Array also performs an inversion of the logic.
 
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