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bettez
24 Posts |
 Posted - 14 Jan 2005 : 12:02:34
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Hi,
we have some kernel code that hangs somewhere and we would like
to use an io pin that we will turn on at different stages to
see what's going on. So far, we managed to use GPIO20 successfully,
but it conflicts with serial port 1 RTS or DTR (dont know which),
and we need to use that serial port.
Is there a gpio pin on the strongarm which is simply unrouted on the bitsy+? We will solder a test wire on the pad and monitor it with a scope.
Thanks |
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bettez
24 Posts |
Posted - 17 Jan 2005 : 15:21:59
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| I was just wondering, are the bitsy+ schematics available somewhere? |
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akidder
1519 Posts |
Posted - 19 Jan 2005 : 19:05:17
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We don't publish the schematics for our products, but I think you'll find the the Bitsy Plus user's manual helpful. Take a look at section 4.1.6. We've got a listing of how all the CPU pins are used.
However, you'll see that there aren't a lot of CPU I/Os available on the Bitsy Plus. It seems like you should be able to use the Serial 1 output lines (TX, RTS, DTR) as long as you don't open the COM1: driver. The only other GPIO I might consider would be the codec reset line (GP11), but toggling it might have unintended consequences on the OS.
The CPLD-driven EIO0-7 lines on J10 are directly tied to the bus and are another good candidate. Perform an 8-bit write to the direction register, 0x1000 0008 (1=output), and write the output value to 0x1000 0000. |
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