SIMtrace hardware

[ml at mail.tsaitgaist.info]

Hi,

I made a lot of changes to the SIMtrace hardware schema.
Here my v0.5 : https://gsm.tsaitgaist.info/SIMtrace/v0.5/SIMtrace.ps

Some important point that are unclear, where I would like to have some
comments :
- I do not use USB_DP_PUP which I found in several at91sam7s design (and
openPCD). I don't know if it will be useful or required.
- I use npn transistor as switches (2 for I/O because bidirectional).
Maybe (N/P/C)MOS is a better solution.

I already bought most of the parts and would like to start drawing the
PCB. Please tell me if you find some errors or have any advices.

kevin