Re: Kernel Debugging Hardware

Alan Cox (
Mon, 12 May 1997 21:20:14 +0100 (BST)

> A parallel port would be easier than a serial one because all you would need
> is a counter and a bit of TTL logic. The parallel port has its own 5 volt
> supply pin, it has several signal pins which can be (ab)used for read and

All you need is an old PC/XT or 286. You raise a chosen output, write the data
byte and wait for an ACK, then repeat waiting for loss of ACK.