I tried the unbuffered jtag programmer, it is partly working. It allows me to go into the device with impact and select various command. For exmaple I can get the device id or checksum, but when I try to erase or program I receive fail. Any ideas?
Second point, why is the buffered device use tri state buffers and not just normal buffers without tristate.
Third point, is impact able to know when the programmer is buffered or not since it seems the buffered one requires more inputs from lpt?
If there are short relections on SCK caused by the cable, the JTAG engine will go astray. Schmitt trigger Buffer suppress those reflections very good, less hysteresis in the buffers will make the suppresion worse. But the external buffers also are kind of slow versus the spped of some JTAG input buffers
It's a way so detect presense of the Adapter and the device.
Don't kno, but also don't think so.
Bye
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