[Coco] Bitbanger port interfacing

[Adam Coolich]

I'm attempting to read/write data from a PC to my Coco3 through the bitbanger port. I've had some success utilizing a terminal program on the Coco3. I'm using Microsoft Visual Studio, which has some easy-to-implement serial communication protocols. Sending data to the Coco is a breeze. However, I'm struggling to overcome the Carrier Detect on the Coco when receiving data. I assume that the Coco is looking for a steady voltage on the CD line to let it know that the "printer" is on (for commands like PRINT #-2 and LLIST). Unfortunately, my programming chops aren't sophisticated enough to overcome this in software on the PC end.

I suppose I could mock up a small breadboard to supply a steady +5V to the CD line, but I'd rather not resort to that.
Is there a POKE that will trick the Coco into thinking that the CD line is active (i.e. printer is on when it isn't)? I've looked through a lot of the available literature on the archive and haven't found anything.

Thanks!
Adam Coolich