I have a 16550A with several stuck channels. One of them is always stuck hi and two other stuck low. I checks the cables on another card and they work fine. When I boot the 16500B into diagnostic mode, the card passes all self diagnostics and it shows that all channels are changing, but when rebooted in to normal mode, the hi channel always shows hi even if I short it to ground. This leads me to believe that the problem is somewhere before the sampling ICs. How likely is it that one of the 1DX5-001 has gone bad? Does the self-diag test these? Is there any part you would suggest I troubleshoot first? Does anyone else have a 16550A with stuck channels that they are willing to sell for parts? Or any known good 1DX5-001 [P]LCC parts?
Thanks,
Harout S. Hedeshian snipped-for-privacy@hedeshian.net