1450 XLD motherboard build, assorted questions

[Shawn Jefferson]

Going through everything on this board, and I had a question, where does Y2 go?  I haven't soldered this on but I have the part X115-ND.  Looking at the pictures of completed boards, and it looks like it's "next" to the two large holes besides the Y1 marking, and it fits here, but I'm not sure, all those holes just look like vias.

 

Also, another (probably dumb) question, should I fill all the vias with solder, or just leave them open?  Continuity seems ok from all the testing I've done.

 

[Shawn Jefferson]

I got impatient and soldered in Y2 where I thought it should go, and I now have signs of life!  Unfortunately I still have some problems somewhere.  I'm getting a picture, which is good, but it's going straight into memory test and showing the first ROM bar as red.  All memory tests pass, and holding down Option shows 48 RAM squares as expected.  Star Raiders cartridge works and I can play (although I don't have sound, but one problem at a time!).

 

I've swapped the OS ROM, reseated the BASIC rom, swapped BASIC rom, checked continuity around the OS ROM a little, tried reflowing the pins on the OS ROM.

[AtarimanElliott]

How far did you get with this project? I am starting one of my own and plan on producing 2 beta units by Feb 1. 2023 

 

-Elliott

[AtariGeezer]

11 hours ago, AtarimanElliott said:

How far did you get with this project? I am starting one of my own and plan on producing 2 beta units by Feb 1. 2023 

 

-Elliott

Are you planning to make a new pcb or do you have a couple of blank 1450XL pcb's?

[AtariGeezer]

On 5/17/2021 at 3:13 PM, Shawn Jefferson said:

Going through everything on this board, and I had a question, where does Y2 go?  I haven't soldered this on but I have the part X115-ND.  Looking at the pictures of completed boards, and it looks like it's "next" to the two large holes besides the Y1 marking, and it fits here, but I'm not sure, all those holes just look like vias.

 

Also, another (probably dumb) question, should I fill all the vias with solder, or just leave them open?  Continuity seems ok from all the testing I've done.

 

Must have missed this post. but Y2 is in a 14pin package and is located to the right of Y1 and just below R132.

[Shawn Jefferson]

Thanks, I did get this part connected and thanks to Bob Wooley I also got the machine functioning for the most part.

 

Except:

• the 1200XL donor keyboard is suffering from the typical mylar issue, I need to get a replacement

 

• the speech synthesis isn't working, I get an error 138 when I try to test this. I haven't really done much troubleshooting on this issue yet, as I'm not sure where to look first. I am running the 800XL OS ROM in this machine, that wouldn't cause this issue would it?  I had assumed that the handlers for V: are being done through the PBI interface.  (V: handler does appear to be present when I run SI on this machine.)

[+kheller2]

3 hours ago, Shawn Jefferson said:

Thanks, I did get this part connected and thanks to Bob Wooley I also got the machine functioning for the most part.

 

Except:

• the 1200XL donor keyboard is suffering from the typical mylar issue, I need to get a replacement

 

• the speech synthesis isn't working, I get an error 138 when I try to test this. I haven't really done much troubleshooting on this issue yet, as I'm not sure where to look first. I am running the 800XL OS ROM in this machine, that wouldn't cause this issue would it?  I had assumed that the handlers for V: are being done through the PBI interface.  (V: handler does appear to be present when I run SI on this machine.)

 

The selftest should speak when you boot with option down.  

[+DrVenkman]

30 minutes ago, kheller2 said:

 

The selftest should speak when you boot with option down.  

He's using an 800XL OS - will that work with this OS?

[AtariGeezer]

11 hours ago, Shawn Jefferson said:

 

• the speech synthesis isn't working, I get an error 138 when I try to test this. I haven't really done much troubleshooting on this issue yet, as I'm not sure where to look first. I am running the 800XL OS ROM in this machine, that wouldn't cause this issue would it?  I had assumed that the handlers for V: are being done through the PBI interface.  (V: handler does appear to be present when I run SI on this machine.)

 

8 hours ago, DrVenkman said:

He's using an 800XL OS - will that work with this OS?

Yes, the 800xl/130xe ROM does work on the 1450, that's what I am using.

 

The V: / T: handler ROM does boot via the PBI interface. 

 

I think these are the file I used...

 

On a side note: I booted mine up a few days ago after replacing the ESC key that had snapped off while moving some 1200xl's and my STacy around.  Thanks to Bob Wooley (bob1200xl) who helped me with the spare parts for that

OSR3V2-416.BIN VTHANB42D.BIN

[+kheller2]

As AtariGeezer mentioned, the 1400 and 1450 boards used standard "BB000001 Rev. 2 (1983-05-10)" OS.

All the wonkiness 1450XLD versions came out in 1984 and were around the TONG time.

Having said that, I now wonder why the 1450 boards were discovered in the wild with OS chips that were (potentially) being modified for the TONG board.