XMOS pin pull-up issue, please help.

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patw
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XMOS pin pull-up issue, please help.

Post by patw »

I have a small hardware issue on the XMOS:

I am using the XMOS XS1 SU1’s X0D52 pin as an input pin, however I am unable to pull this pin HIGH using a normal MCU in push-pull (strong pull-up) mode, the MCU can put out 20mA in this push-pull mode but still can’t pull this XMOS pin HIGH, I can only get ~0.7v onto this pin.

How can I pull this pin HIGH? Is there a setting in the XMOS to make this pin easier to be pulled-up?

Many thanks,

PW


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Ross
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Post by Ross »

X0D52 is part of port 32A. Are you sure you have enabled this port as in input port?

Sounds like you might be driving a 0 on this port.
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Folknology
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Post by Folknology »

Are you sure about the 20ma, I thought Xmos GPIOs had either 4ma or 8ma capacity (4ma for the larger ports and only selected 1 bit ports have 8ma), or am I missing something?

regards
Al
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segher
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Post by segher »

It is the external device that has 20mA drive strength :-)
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