Hi all, I have a developed a fault with the serial comms board, can send from control to pc on both channels (confirmed using Print Program in conversational mode), but cannot send from pc to control on either channel. No errors, just indefinately "Busy reading leader" until I give up.

Previously I had this problem on one port but the second worked ok. Now after not having used the machine in a few months neither are working.

I have ruled out the pc and the cable.

I have tried replacing the two socketed MC1489's and the one soldered one individually with no improvement. I know this is far from conclusive but I only had one spare on hand so I suppose it's worth mentioning!

Anyone have any ideas?

Thanks, Gregor