I'm copying this from threads I had posted to the IIgs group on Facebook. I'm posting this here as it's much easier to find content here than on FB). Even though I didn't end up solving the issue maybe some of my troubleshooting will save someone else time...
I just finished moving some hardware from one IIgs to another. The new IIgs has a TWGS, 4MB RAM, Microdrive Turbo, Uthernet II and a PCTransporter. The PC Transporter was previously in a different IIgs (which had an AppleSqueezer and an CFFA3k). Last time I booted the PCTransporter (which admittedly was a while ago and wasn't before moving from the prior IIgs to this IIgs) it worked just fine. Now when I boot it, I get the PCTransporter screen, the memory test happens but when I should start to see DOS start to boot it's like the IIgs monitor goes out of range. Restarting the computer gets me back into GS/OS.
I don't see any documentation suggesting that the TWGS doesn't work with the PCT (both are AE products). I am wondering if it's an issue with the ColorSwitch but that's also odd as it does switch to PCT mode, the screen just goes black-ish when DOS should boot. (As an aside I can't get into the PCT control panel either).
Checking if any PCT experts have any thoughts?
As an aside, when I was playing around with this I turned off the Appletalk IRQ setting in the TWGS DA - that left me with an "Unclaimed Sound Interrupt 08FF" error on boot. I thought I was going to have to do some hardware troubleshooting but turning that setting back on (I was able to still boot the system after doing a CTRL-OA-RST when the error came on) and it started working again.
I also just tried playing with the dials on the back of the IIGS monitor to see if I could get the screen to display something (as it does seem like a video single is coming across it just can't sync), but no luck.
As an update, I used the information on this site (https://github.com/patdie421/pct-connectors-rebuild) to build a connector so I could connect the PCT to my IBM 5153 CGA monitor and rule out this being an issue with the ColorSwitch. Same issue happens, the PCT splashscreen comes up, as does the memory test, and then the screen goes blank. For good measure, I did take out my Microdrive Turbo and replaced it with my CFFA3k and still no change. I have confirmed the PCT is not crashing though as I can exit back to Prodos by pressing the key combination to get to the control panel and press 5 to exit to prodos. I can't actually see the menu when I'm doing this, I'm just following the menu layout based on the PCT manual though.
I have confirmed the PCT *IS* working fine - I put it back into the other IIgs with the AppleSqueezer and it's working.
Some theories I tested but dispelled:
* Driver issue as the PCT was configured to use one of the IIgs ports as a serial port but I had installed my Uthernet II in slot 2 as the TWGS is in slot 3. Not the issue - I pulled the Uthernet II, played around with the my card settings and ended up installing the Uthernet II in the IIgs that was working with the PCT and had no issues.
* Tried all manner of changing TWGS settings (including speed settings). No change
* Using my working IIgs I figured out what keys to press to reset the full PCT driver configuration in the control panel (working with a black screen). No change, but at least once after resetting the PCT blindly through its control panel I did get a scrolling "Disk Read Error" message which was from DOS but again it was continuously scrolling like it couldn't sync.
I will not be pulling the TWGS as that is a bit more than I'm willing to do so I will keep the PCT in my other IIgs. I'm going to conclude the issue is either: Some sort of weird incompatibility with the TWGS (even though they are supposed to work together. I will note that mine is one of the faster RM versions. Alternatively maybe there is some sort of power issue (i.e. the PCT running with the TWGS). Even though I have a souped up, higher wattage PSU, I haven't changed the wires, so possible a voltage drop issue.
I just finished moving some hardware from one IIgs to another. The new IIgs has a TWGS, 4MB RAM, Microdrive Turbo, Uthernet II and a PCTransporter. The PC Transporter was previously in a different IIgs (which had an AppleSqueezer and an CFFA3k). Last time I booted the PCTransporter (which admittedly was a while ago and wasn't before moving from the prior IIgs to this IIgs) it worked just fine. Now when I boot it, I get the PCTransporter screen, the memory test happens but when I should start to see DOS start to boot it's like the IIgs monitor goes out of range. Restarting the computer gets me back into GS/OS.
I don't see any documentation suggesting that the TWGS doesn't work with the PCT (both are AE products). I am wondering if it's an issue with the ColorSwitch but that's also odd as it does switch to PCT mode, the screen just goes black-ish when DOS should boot. (As an aside I can't get into the PCT control panel either).
Checking if any PCT experts have any thoughts?
As an aside, when I was playing around with this I turned off the Appletalk IRQ setting in the TWGS DA - that left me with an "Unclaimed Sound Interrupt 08FF" error on boot. I thought I was going to have to do some hardware troubleshooting but turning that setting back on (I was able to still boot the system after doing a CTRL-OA-RST when the error came on) and it started working again.
I also just tried playing with the dials on the back of the IIGS monitor to see if I could get the screen to display something (as it does seem like a video single is coming across it just can't sync), but no luck.
As an update, I used the information on this site (https://github.com/patdie421/pct-connectors-rebuild) to build a connector so I could connect the PCT to my IBM 5153 CGA monitor and rule out this being an issue with the ColorSwitch. Same issue happens, the PCT splashscreen comes up, as does the memory test, and then the screen goes blank. For good measure, I did take out my Microdrive Turbo and replaced it with my CFFA3k and still no change. I have confirmed the PCT is not crashing though as I can exit back to Prodos by pressing the key combination to get to the control panel and press 5 to exit to prodos. I can't actually see the menu when I'm doing this, I'm just following the menu layout based on the PCT manual though.
I have confirmed the PCT *IS* working fine - I put it back into the other IIgs with the AppleSqueezer and it's working.
Some theories I tested but dispelled:
* Driver issue as the PCT was configured to use one of the IIgs ports as a serial port but I had installed my Uthernet II in slot 2 as the TWGS is in slot 3. Not the issue - I pulled the Uthernet II, played around with the my card settings and ended up installing the Uthernet II in the IIgs that was working with the PCT and had no issues.
* Tried all manner of changing TWGS settings (including speed settings). No change
* Using my working IIgs I figured out what keys to press to reset the full PCT driver configuration in the control panel (working with a black screen). No change, but at least once after resetting the PCT blindly through its control panel I did get a scrolling "Disk Read Error" message which was from DOS but again it was continuously scrolling like it couldn't sync.
I will not be pulling the TWGS as that is a bit more than I'm willing to do so I will keep the PCT in my other IIgs. I'm going to conclude the issue is either: Some sort of weird incompatibility with the TWGS (even though they are supposed to work together. I will note that mine is one of the faster RM versions. Alternatively maybe there is some sort of power issue (i.e. the PCT running with the TWGS). Even though I have a souped up, higher wattage PSU, I haven't changed the wires, so possible a voltage drop issue.
