On 15 Apr 2012, at 18:47, David Forbes wrote: > The generic ports are TTL, but when they get configured for I2C, they become > open-collector. I2C requires the pull-up resistors to implement its tricky > protocol over two wires. > > You'll have to find the room for them. If it helps, 1/8 watt resistors are a > bit smaller than 1/4 watt resistors.
I am not using pins that can be configured as an I2C bus per se, but using two ordinary TTL level pins. Is the issue that there is some intermediate state between high and low that will send the whole mess haywire if I don't have a default condition set via resistors? If only Farnell in the UK sold a resistor with wires that are 1/8w, but I cannot find any. If Farnell deliver my Raspberry Pi tomorrow as promised I will be a happy bunny. I seem to have been allocated one of the first 700 - Farnell got 700 and RS got 700 last week. That means the Pi Foundation have held back 600 of the initial 2,000 that came to the UK. Presumably these are being sent out to developers who are doing all the educational software development in readiness for the start of the new school year in September. John S -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. To post to this group, send an email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/neonixie-l?hl=en-GB.
