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About Nezgar

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  1. Hmm, that's a possibility I didn't about... The 27256 I sent @Crc_Error would have been 120ns, and an a8diag on a 100ns 27128. I have burned many XEGS ROMs that worked successfully and I'm sure they were the same type. Regardless, maybe I'll dig around and see what I have that's slower to see if that makes a difference.
  2. @Beeblebrox Woops, you are right somehow I assumed US doubler in my mind while writing - never mind that then! So that's good in this sense because you can use Atari's 1050 diagnostics ATR for sure in the Happy drive if you temporarily place a 1050 stock ROM & CPU into that drive. The one picture above with the ROM IC with part number 94132B-2131 "Tandon" is revision "L" and will work with either the 2793 or 2797 WDC controller. EDIT: important!: If swapping the Mask ROM into a drive that previously had an EPROM, make sure to check the JP1-4 jumpers above the socket are configured & moved appropriately: JP1 & JP3 jumpered for a Mask ROM (We can see this in the stock drive pictured in the original post) JP2 & JP4 jumpered for a 2732 EPROM (We can see this in your happy drive)
  3. One of the signature features of happy drives is full-track buffering. This will throw off many copy protection checks that rely on specific timing. The solution is to boot the happy utilities disk, press 1, then 1, to set the drive to "unhappy mode" - which disables the track buffering and access to the extended commands. This will allow most copy protection checks to pass. This should not be an issue on your drive with the US Doubler mod, as it doesn't support track buffering. You will not have success using the original Atari 1050 Diagnostics with happy or US Doubler modded drives, unless you "downgrade" to a stock 1050 ROM. There is a tool to upload a relocated version of the stock 1050 to the Happy RAM to temporarily "convert" it - but I have found that this also doesn't work when using the 1050 diagnostics software - one of the test commands throws the drive into an on/off failure mode. For the happy drive, you can use the diagnostics menu in the happy utility for basic ROM/RAM and RPM tests. For the US Doubler, you can use the RPM utility included in some distributions of SpartaDOS 3.2, and others. It's a 2764 (8KB) EPROM. ?784 would mean produced ?7th (so could be 7th, 17th, 27th, 37th, or 47th) week of 1984. Most 1050's used a 2793 controller. Later drives used a 2797 controller. Pin 25 is for is side select when using double-sided drive mechanisms, so it's not needed for the single-sided 1050. In stock 1050's, the later revision "L" ROM is needed to work with this controller due to a slight change needed in the commands sent to the FDC.
  4. I'm not sure, but the SpartaDOS X manual lists error 150 as "150 Sparta: Directory not found" Maybe try variations like D1:STACK.ASM 1:STACK.ASM D1:>STACK.ASM 1:STACK.ASM Or other devices like E: P: C :
  5. When BASIC is enabled, it "replaces" 8K of RAM. If you hold option on powerup (XEGS might be slightly different), it should disable BASIC and show 48 blocks in the memory test. The last 16KB of RAM "under" the OS ROM is not tested.
  6. @TGB1718 600XL, 800XL, 65XE, 130XE, 800XE use a 16KB OS ROM and a separate 8KB BASIC ROM. So a 16KB 27C128 type eprom is appropriate. XEGS also adds 8KB BASIC and 8KB Missile command to a single ROM, so 32KB, or 27C256 should be fine.... 27C256 is normally a drop-in replacement with no jumper or pinout changes necessary in the XEGS so I'm not sure why it's not working yet in this case. A 16KB OS should also work, but BASIC and Missile command won't work since they'll mirror parts of the 16KB OS.
  7. The physical drive modification The modifications were first described by Bob Woolley in the January, 1989 issue of Atari Interface Magazine "Inside the XF551 Disk Drive" page 7 (page 8 in the PDF): https://archive.org/details/atari_interface_jan89/page/n7/mode/2up Here's a text version: https://www.atariarchives.org/cfn/05/07/0063.php
  8. Good work @Beeblebrox! I love fixing up 1050's myself as well, and have acquired drives that needed most of these same repairs. The best were drives that had AUTHENTIC happy computing made boards, which for all of my "classic" atari life I had never actually seen in person. Now I have two. This post has various happy utility software disk images, including 7.1: https://atariage.com/forums/topic/283666-archive-of-happy-backup-software/?tab=comments#comment-4544843 One thing to check for is when doing the ROM test using the diagnostics option, ROM version 1 will say "PASS" and ROM version "2" will show "Pass". @E474's dump tool is definitely a conclusive way to dump the ROM without having to desolder the EPROM, though that is even better if you have confidence in dessoldering skills since it can extract 4 bytes that a software dump can't. Your "pirated" board has a single SRAM chip, so that big 28 pin chip with the top scratched off is most definitely an 8Kx8 6116 SRAM chip. Early genuine happy boards had 6KB of ram across 3 2Kx8 SRAM chips, so at least functionally you have the 8K to run all the "fun" stuff like tools that upload code to the drive to make it operate as an Archiver, US Doubler, or Stock 1050. aaaaaactually it increases memory from 256 bytes to 384 bytes A stock 1050 has 128 bytes for the stack (in the 6810), and 128 bytes for the sector buffer (in the 6532).
  9. Turn off the drive, then turn it back on. Or install a reset button like this:
  10. Heh - very likely. Those adapters solve a plethora of EPROM compatibility challenges. Likely I was talking about the older simpler 2364 adapter that greatly simplifies replacing the BASIC "B" 2364 in XL's with a 2764, and optionally up to 8 selectable BASIC replacements when used with one 27512 EPROM. Fun stuff. https://store.go4retro.com/2364-adapter/
  11. No convenient drop in replacement... a 2516 helps with the pinout being closer to the 2316 mask ROM, but from my own experience getting a 2532 working in a 1050, you still need to invert the CS /OE input(s) in some combination to make it work.. I'll save you from any further grief and research effort -- just get one or more of these: http://www.go4retro.com/products/23xx-adapter/ Take a 2764 type eprom/eeprom/flash etc, and easily make it "emulate" any combo of 2316, 2716, 2332, 2732, and 2364, and optionally active low chip select. Replacing the 2KB floating point ROM, you could hook up the optional address lines to "bank switch" up to 16 alternate 2K ROMs with one chip 😆.
  12. Good to hear! Might be worth cleaning the legs of the "bad" chip and seeing if the simple fact of removing/reseating it gets it working again in case it was just a continuity problem on the pins or socket. Also test it in another computer as a last measure before tossing it...
  13. Since you say it can't read anything, it makes sense that after the 40 steps, the next phase is a verify, which is to read what it just formatted, and then should step back 40 steps - but a failure here will jump all the way back to track 0, further supporting that it can't read anything. 1050 nominal is RPM 288RM. XF551 is 300RPM. Though you will be unable to perform an RPM speed test if it can't read anything, hence the erronous report of 3000+RPM... One thing that would be good to know is with a disk already formatted good on a 1050, then formatted (and failed) in the XF551, put the disk back in the 1050 and see if the contents are still readable, or if they have been erased. This will tell us if the erase/write function is doing anything in the XF551. I'm also thinking that the "easiest" next step would be to swap out a different mech into the unit, to see if the problem is with the controller board, or the mech, but I realize this may be difficult if one doesn't have a spare mech, and bare DD 5.25 mechs are hard to come by and pricey... Edit: a couple other random thoughts: cleaning heads may be in order. also check the power outputs are at/close to 5.0V and 12.0V.
  14. Are the lines moving/jittering, or fixed/stationary? I wonder if you play with the vertical adjustment knobs. IIRC some can be adjusted without opening:
  15. Yes, the PCB's for these three 64K bankswitching carts are the same I believe, the main difference in the GAL that places the control register at slightly different addresses so they can each be individually controlled: banking and turned on/off. I got some repros from kenames99 a few months ago, yet to burn the requisite eproms and test though.
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