Jump to content
IGNORED

130XE needs help


Recommended Posts

I have an Atari 130XE that boots but has problems. When it boots it has green horizontal bars that rapidly flicker like an old TV with the vertical hold out of adjustment, with a Star Raiders cart installed, the screen shows a screen full of white and light blue characters. I am including photos. The characters really aren't readily visible in the photos. Chip switching is very difficult because 130XEs are not socketed. I would like to have a good idea where I could start adding sockets to switch some chips.

post-61328-0-56493900-1522635083_thumb.jpg

post-61328-0-21656100-1522634949_thumb.jpg

Edited by hueyjones70
Link to comment
Share on other sites

Changed out the ANTIC screen cleared up and went straight to self test. Mem test would go to 15 blocks all green then blank screen. I did the resistor cross deal then every other square was red. Now I am working on adding sockets for new RAM.

  • Like 1
Link to comment
Share on other sites

Now that I have replaced all of the RAM, I am back to a dead screen, no color or anything else. I get a flash of green when I turn the computer on. Plugging in Star Raiders makes no difference. I will start trouble shooting with my volt meter in the near future. I now have an almost completely socketed 130XE that doesn't work.

Link to comment
Share on other sites

Checked all the voltages on the main RAM bank and found 3 places where I had lifted traces, repaired those with wire. Now the 130XE is back to immediate Memory Test on boot, RAM blocks 1-15 show green and at RAM block 16, the screen goes blank. Star Raiders does boot. Any suggestions NOW.

Link to comment
Share on other sites

Checked all the voltages on the main RAM bank and found 3 places where I had lifted traces, repaired those with wire. Now the 130XE is back to immediate Memory Test on boot, RAM blocks 1-15 show green and at RAM block 16, the screen goes blank. Star Raiders does boot. Any suggestions NOW.

 

I would check if all addresslines are proper connected to Freddie. Check A0...A15 from CPU´s pins to Freddie´s pin with your DMM. Start with A15 and count down, because I would suggest A13 is not connected through.

Link to comment
Share on other sites

I found the problem. The computer would boot Star Raiders and during my trouble shooting I touched the Freddie and the screen went crazy. I then started checking voltages on Freddie's pins. When I would touch the 3rd pin from the right on the top row the screen would output random graphics characters. I followed a trace from that pin to the IC directly above it then installed a jumper on the back side of the mb, now everything works.

  • Like 2
Link to comment
Share on other sites

Since I now have a fully socketed mb, I am thinking about doing the 320K upgrade, where can I find a good set of instructions?

Here's a BBS file I had on my machine:

 

 

by Scott Peterson
(modified by Tom Harker of ICD 01/25/86)
 
After reading and building both the 800/288K upgrade (D.G. Byrd), and the 800XL/256K upgrade (C. Buchholz), I decided that there had to be a way to upgrade the 130XE. There is and thanks to the "FREDDIE" chip (C061991), this modification was much easier to design than either of the other upgrades.
 
Since all ICs are soldered directly to the board on a 130XE, installation requires excellent soldering and de-soldering skills.
 
PARTS LIST
 
 
 
 Quantity    Type        Description
 
    1       74LS158    2 to 1 Multiplexer
    8         41256    256K Drams (150ns)
    1                  33 ohm 1/4 Watt Resistor
    8                  16 Pin Low Profile Sockets
 
DOIN' IT
First remove both the case and the metal shield to get down to the motherboard. Then de-solder and remove the eight RAM chips U26 through U33 (MW264). They are the inside row (closest to the TV RF module). Next, replace these with the sixteen pin low profile sockets. Take your new 256K DRAMS and bend pin 1 straight up on each chip. Plug these chips into the sockets you just installed. Now take a piece of wire approximately 12 inches long and solder a jumper from pin 1 on each of the 256K RAM chips so they are connected together.
 
Next, cut and bend up pin 15 on the U23 (C014795 the PIA) or instead, remove R286 (closest to pin 20) and cut the foil trace running from pin 15 towards the front of the board. Take your new 74LS158 and break off pins 5, 6, 7, 9, 10, 11, 12, 13 and 14. Bend up the other pins except for pins 8 and 16. Install this "piggy-back" on top of U20 (HD4050 - located just to the right of C50) and solder pins 8 and 16 of this 74LS158 to pins 8 and 16 of U20. Now connect pin 15 (74LS158) to pin 8 (ground) with a short jumper wire.
 
Take a piece of wire about 4 inches long and solder one end to pin 38 on the chip marked C014805 (this is 02 on the GTIA) on the motherboard and the other end to pin 1 of the new 74LS158. Next solder a wire to pin 15 (the one you bent out) of U23 (PIA) and connect the other end to pin 2 on the new 75LS158. Solder a wire to pin 16 on U23 and connect the other end to pin 3 on the new 74LS158.
 
Take a 33 ohm 1/4 watt resistor and trim the leads to about 1/4 inch. Solder one end of it to pin 4 of the new 74LS158. Connect a wire from pin 1 of the new DRAMs (any one of them) to the other end of this resistor. Re-assemble the RF shield making sure you are not shorting it to any of the modified hardware. Assemble the case and you finished.
 
 
USIN' IT
The best deal for this mod is to use SpartaDos (availiable with SpartaDos Construction Set or the US Doubler). The new RD.COM file supports it as a full 256K RAMdisk (any drive number) or a 192K RAMdisk with 64K reserved for BASIC XE. This 320K modification is also totally compatible with ICD's RAMBO XL mod, for the 800XL and 1200XL computers. Questions on SpartaDos with this mod and RAMBO XL will be answered on ICD BBS 815-968-2229, 24 hours, 300/1200/2400 baud.
 
MYDOS 4.0 also supports a very large single density RAMdisk. With BASIC XE you can use a 1500 sector RAMdisk and without it you can have about 2000 sectors.
 
If you are a hot-shot programmer (I'm not) I think a printer spooler that uses part of this RAM would also be very nice. This mod is easy to do and perfect for running BBS. One note, on COMPUSERVE, there is a mod by Rich Andrews which should not be confused with this one. His uses 33 new chips and mine uses only 9 new chips.
 
320XE MEMORY CONTROL REGISTER 54017 ($D301)
 
 
 
Bit 7 6 5 4 3 2 1 0
    D a b C c d B R
D=0 enable diagnostic ROM
B=0 enable BASIC ROM    
R=1 enable OS ROM        
C=0 enable extended RAM
abcd=memory control bits
 
   Bank #      Control #
   Bank 0 ------->131
   Bank 1 ------->135
   Bank 2 ------->139
   Bank 3 ------->143
   Bank 4 ------->163    Basic=Off
   Bank 5 ------->167    OS   =On
   Bank 6 ------->171    ENH  =On
   Bank 7 ------->175
   Bank 8 ------->195
   Bank 9 ------->199
   Bank 10 ------>203
   Bank 11 ------>207
   Bank 12 ------>227<--\
   Bank 13 ------>231    \ 130XE
   Bank 14 ------>235    / BANKS
   Bank 15 ------>239<--/
 
If you are using MYDOS 3.016 and wish to use BASIC XE and a RAMdisk at the same time, boot DOS and Poke 5275,16. Go to DOS and write new DOS. This will keep the two from "bumping" into each other. A similar poke can be done to DOS 2.5. It is Poke 4838,163. The handler I have will set up 192K of the extra RAM as 2 SD RAMdisks or 1 DD RAMdisk.
 
This upgrade has been built and tested on a BBS. It has run for days on end without a memory loss or error. If you need help or more information, feel free to call the Peanut Gallery (408) 384-3906 24 hour, 300/1200 Baud. Leave mail to the Sysop (that's me). Good luck and let me know if you write a better handler for DOS 2.5.

 

 

I hope it's accurate. I remember when I finally got around to doing this mod on my original from 1988 130XE (this would have been sometime in 2000s), there was an error in a single pin (I believe the connection to GTIA) of my instructions. I don't recall what I used to do this however.

  • Like 1
Link to comment
Share on other sites

  • 3 months later...

I recently found a 130XE that I had put in a box years ago and someone had put pillows on top of it so I had forgotten all about it. When I hooked the computer up and turned it on it went directly to memory test and on the top row, the blocks were alternating green, red, green, red etc; the 2nd row was all red except for two green blocks, and the third row had mostly red. I decided the memory must be bad so I took out the main RAM bank, installed sockets, and installed new RAM chips. Now when I boot the computer, I get a black screen. No change when I boot with Star Raiders. I crossed the RAM resistors and rebooted. Now I get top row G,G,G,R in a repeated sequence, 2nd row has R,R,R,R,G,G,R...…, 3rd row has G,G,G,R,G,G,G,R. Star Raiders boots. I probably should have considered something else besides replacing the RAM. I checked voltages on all of the RAM pins and they are mostly consistent so I know I didn't lift any traces. Could the memory control chip be the problem, ANY SUGGESTIONS.

Link to comment
Share on other sites

that harker revision has pin 38 when it should be pin 30 !!! I'm not so sure that's cool or kosher...

 

I'm not a fan of the cut the pin no sockets scratch the traces break pins off method outlined in that mod either....

 

use sockets (if it says optional take the option) try this one I did to my own back in 90 whatever, it's my daily driver to this day...

 

http://atariage.com/forums/topic/281132-atari-130xe-4164-best-replacement-or-upgrade-ram-chips/?p=4079782

Edited by _The Doctor__
  • Like 1
Link to comment
Share on other sites

that harker revision has pin 38 when it should be pin 30 !!! I'm not so sure that's cool or kosher...

 

I'm not a fan of the cut the pin no sockets scratch the traces break pins off method outlined in that mod either....

 

use sockets (if it says optional take the option) try this one I did to my own back in 90 whatever, it's my daily driver to this day...

 

http://atariage.com/forums/topic/281132-atari-130xe-4164-best-replacement-or-upgrade-ram-chips/?p=4079782

When I finally did my Peterson upgrade, it took some time debugging it. Help from Atari Age members found the pin 38 vs pin 30 issue. I believe it was down to an OCR scan mistake.

Link to comment
Share on other sites

I have found that when I flex the MB diagonally the self test stops and the screen turns comepletely blue, no border. All of the RAM chips that were placed in sockets checked out OK in another computer. I have looked for broken or cracked traces and haven't spotted any. The memory test never gets to extended memory.

Edited by hueyjones70
Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
 Share

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...