Picaxe 18 Bidir pin
- Thread starter fretei
- Start date
westaust55
Moderator
The manuals will tell you which pins are used by i2c.
So read the register mentioned and just set the pins you need to alter to be changed to outputs while leaving the others alone.
or
Are you looking for a full 8-bit/pin wide port for parallel operations ?
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hippy
Ex-Staff (retired)
It's certainly possible to but whether it will work or even cause damage to your chips depends on how you do it and what you are trying to achieve.
Some more details on what you are trying to do will help people here give better advice.
kranenborg
Senior Member
Based on hippy's findings as referred to in the second post, I delivered some tested code snippets for bidirecional I/O as well as to additional ADC inputs on the 18X in the Code Snippets section of this forum ("Extending / reconfiguring Picaxe-18X I/O"): http://www.picaxeforum.co.uk/showthread.php?t=9289
Like mentioned by fretei, this option will probably not work if i2c is used, as I expect that the picaxe will then revert to the standard inputs and outputs configuration (I have not tested though)
@hippy: You mentioned in another thread that the 14M will have the potential for 8 ADC channels. Is there a similar "shadow" register for the 14M as there is for the 18X? In that case the same type of code could probably be used to enable all eight channels
/Jurjen
Like mentioned by fretei, this option will probably not work if i2c is used, as I expect that the picaxe will then revert to the standard inputs and outputs configuration (I have not tested though)
@hippy: You mentioned in another thread that the 14M will have the potential for 8 ADC channels. Is there a similar "shadow" register for the 14M as there is for the 18X? In that case the same type of code could probably be used to enable all eight channels
/Jurjen
westaust55
Moderator
i2c keeps switching the data pin to be an input and an output - particularly for read comamnds. This is being done without affecting the other pins as inputs so seems possible that other non i2c pins can be made outputs and remain unaffected by i2c.
But fretei states "I need a bidirectional port"
Taking the word port literally he could be looking for 8-bit wide port as opposed to a single pin. Awaiting his clarification there.
But fretei states "I need a bidirectional port"
Taking the word port literally he could be looking for 8-bit wide port as opposed to a single pin. Awaiting his clarification there.
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