Dropcheck

The modem and speech were working physically prior to the PAL C Code change on this and the newer version 1.4 boards. So at worst a revert back to the original PAL C code would fix any issues with them. Running the different /Extend signal to the PBI pin 38 would not have changed that as long as there is no ID conflict. Both @reifsnyderb and I are kind of waiting on parts at the moment to continue troubleshooting. I sent my only set of power cables with the v1.3 board. Hopefully the Digikey order with the component parts will arrive Wednesday or Thurs. It's almost a race to see who will get their parts in first. 😔🙂 @mytek if your VOIP device has a actual RJ11 jack on it, then it should work. I used this ATA device with a low cost pre-paid level of service from this company to test the modem. My config in the ATA device did not allow the dialed tn number to connect, but the modem behaved as it should when the connection could not be made. I was getting a busy signal piped into the audio out from the ATA device. The modem disconnected after about 15 busy tones.

@psycho you might ask @Albert to see if he can move this thread to the main Atari 8bit forum. It will get much more attention there. Still waiting to get my 1450XL board completely done to use your board in testing.

Count me in for at least $20.

It is entirely possible that the 1450XL is inherently a bit flakey as far as external PBI devices are concerned. For instance I had one of @AtariGeezer 's version C IDE Plus 2 boards and couldn't get it to come up with a config screen. Yet when I returned it back to him, he says it booted right up on his 1450XL. Supposedly that version you can't change the PBI ID, so it wouldn't necessarily be an PBI ID conflict. At one point in my troubleshooting with this version, I replaced all the PBI buffer chips with faster ones. No change. I even cut the unbuffered PHI2 signal to the PBI connector and ran a buffered one to the same pin. Still nada. At some point in troubleshooting a problem you can start chasing your own tail and make no progress at all. Hopefully with another person eyes and equipment and the same board, a better picture will arrive.

Let's see what @reifsnyderb sees on my board and his pbi devices. I've still got the v1.4 replica that I can fiddle with on my IDE Plus 2.0 v F. It's still a possibility I'm missing something. If my F version is set to ID 1 by default, that would conflict with either the builtin modem or the voice chip. If @AtariGeezer 's version C is set for 0 by default, not sure the creator would up and change the default PBI ID from one version to another though. 😔

I took another look at the Atari schematics and retraced the original Atari bare board. I'm not ohming out any difference in the way I currently have indicated in my 1450XL replica schematic. The original board has PBI pin 38(Extend) connected to U23 pin 10/U33 pin 6(Early Extend). ~EXTSEL PBI pin 2 is pulled high by R47 and goes to U11 pin 6 and U25 pin 3.

I've tried both the original Freddie and the replacement Freddie. No change. I will take a look at Extsel/Extend again to see if there is a signal inversion that shouldn't be.

FYI: The Atari 1450XL Replica Board is almost done. Here's a Youtube video showing the current state. Basic tests completed. One major feature is still pending. External PBI devices are currently causing my 1450XL Replica board to freeze or crash. @AtariGeezer is reporting that he has no such issue with his Atari 1450XL original prototype board, so it appears to be an issue only with mine. I know it's been a long road to get to this part and a lot of time spent waiting by one and all. I would like to take a little more time and allow @reifsnyderb a crack at troubleshooting my v1.3 proto board to see if he can determine why and/or a fix before I release gerbers/BOM etc. He's much more knowledgeable about PBI devices than I am. Hopefully it is something relatively simple.

No change.

Okay, maybe the Atari 1400XL schematic is wrong, but there's no other pull-up resistors for the U15 input IRQ/RDY lines in the Atari 1400XL schematic. Page 6. I've accounted for all the resistors in @Vandal968 's BOM. So it would seem the Atari schematic is correct. It might not be good practice though. 😬 Atari1400XLSchematic.pdf

There is a resistor R24 tied high on the first sheet next to the CPU U16 for the RDY signal. Just above it is another resistor R40 tied high for the ~IRQ signal. Sorry about the scattered parts, Diptrace can handle distributed signals, but it's easy to miss when you are looking at multiple sheets of paper. 🙂

The newest schematic is just the various fixes on the old v1.3. Nothing else really changed electrically. The issues were also happening with the older version 1.3 board with the fixes applied. Fixes: 1. Tie R100 to +5V instead of GND 2. Tie R134 to +5V instead of GND 3. Take L5 and place in line with +5V to J8-15 4. Tie SW2-3 to GND 5. Tie RP1-4 to U36-26 6. Tie U25-37 to U35-8 7. Flip orientation of Q8 --Emitter to R140, Base between R140 and R141, Collector to R61 8. Remove *T1 1450XL_v1_3.pdf

I could, but I am scared of torching his board. 😬 Besides I don't think it is the IDE PLUS v2 F board. I'm getting the same behavior on all external PBI devices I've tried. So it would seem to be with my remake. I just don't know why.

I would have to say I am building the 1983 Dynasty short board. Or in other words the pre-TONG version.

It has a floppy drive connector on the inside, and I've seen in a couple of AtariAge posts that one or two people were able to connect an XF551 drive and get it formatted and read. I don't remember if it was the TONG version motherboard or the one I'm testing. It works fine with an XF551 connected via the serial port. It does use the 1200XL keyboard.