Are there some tests that can be done to verify the operation of an Orange Micro Grappler+ printer interface card (1982) in an Apple //e? I've searched around the web and the paper manuals for solutions or debugging ideas but haven't landed on anything definitive.
Issue A - Grappler+ is in slot 1 and my understanding is that PR#1 should direct commands to the printer and PR#0 should return to screen output. Instead PR#1 (or PR#2 when in slot 2) makes the //e unresponsive to everything except ctrl-openapple-reset. This is the case whether or not the ribbon cable is attached to the card.
Issue B - If PR#1 is invoked and printer is on (regardless of paper inserted or printer 'select' status or any other printer buttons) "NOT SELECTED" flashes on screen and there is a constant fast beep until the printer is turned off. I don't know if this signals a card issue or a printer issue or something else.
Printer details - The printer is an Apple ImageWriter II. It successfully passed the self-test, the printer buttons do what they're supposed to (line feed, etc.) and I can successfully print from Windows PC (generic driver) via USB (plus a couple adapters to attach to the serial printer cable). Everything seems to work properly.
General details - I have always changed cards and cables with the power off. Tried Grappler+ in slots 1 and 2. I reviewed the Grappler+ operating manual and set the DIP switches (tried a few variations). I'm using an IDC to DB25 ribbon cable (red to left/center/away from pin 25) on the card, and a serial printer cable (same one as for the USB test above). Tried with and without 80 column card in slot 0. Tried with DOS 3.3, and ProDOS 1.1.1/AppleBasic 1.1.
I grew up with an Apple //e and knew the details fairly well, but after so many years this one has me stumped. Thanks for any tips you can provide.