Thanks Clive, Dean is a likely supplier if I do go for the UC300 hopefully he will spot this and comment as from reading this forum he has a wealth of knowledge and his posts have been a huge help getting me where I am with this.

Tomorrow is a day of testing as although the PC has died I want to be certain it wasn't a result of something going wrong in the machine and sending a death ray back through the parallel ports. first check is voltages on all pins then manually introducing signals to test all the axis function correctly. as long as this all tests ok then hopefully adding the motion control will be a fairly straightforward process.

while I am fairly sure the PC's death is just bad luck I want to be sure before adding anything new just in case