Mindboards

I want to modify the neat little PFC8574 mini board I bought from futurlec.com by adding a RJ12 input socket.

I have prepared a diagram showing where I think the wires should go but would appreciate it if someone could look at it and advise of any errors before I start work.

The socket will be placed on top of the board and all the wiring carried out underneath to leave the original input arrangements untouched. The board has built-in pullups (jumper selectable)but they are only 10k so I will not be using these.

I didn't double check the wiring on the PCF8574 board against Futurlec datasheets, but it all looks fine to me. If you don't have exactly 82K resistors, I've had success with everything from 10K to 100K and Matt has used up to 470K on short data buses. It is preferable to stay between ~30K to ~100K though.

Thank you very much for such a fast reply. I have already bought a pack of the recommended resistors so I can get started straight away.

Glad to help. It's always fun to see other people create custom hardware, especially when they come up with the same old thing, but put together in a different way. The PCF8574 is a pretty versatile chip, especially when you use your imagination. Stay tuned for a project of mine that uses the 8574 in a slightly stranger-than-normal manner.

Stay tuned for a project of mine that uses the 8574 in a slightly stranger-than-normal manner.

A very small hair brush for a pet hamster? You'll have to hot glue a small handle to the DIP package.

- Xander

mightor wrote:A very small hair brush for a pet hamster? You'll have to hot glue a small handle to the DIP package.

Haha, very funny. The only pets I have are some (usually) 20+ birds and they take care of combing themselves.

Now that is a scene I would love to see!