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About CommodoreDecker

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  1. Thanks! I had set the system to accelerator mode, but it still flipped into self-test mode. (The ROM was removed from the mobo and put into the Rapidus expansion socket, of course.) Your 3 points probably explain everything-- and I did have to power off the XL, sit there whistling the theme to "The Brady Bunch" to ensure nothing was residual in RAM after 1 minute 9 seconds, then powered up again and got different and inconsistent results. 1) Yeah, something seemed a bit wonky and loose. I suspect that alone may be sufficient as the cause (if not for not being able to exist with RamboXL). The ROM chip was the only one to fit solidly in its new socket. The Rapidus board's pins would not stay put and easily moved about. Strange that the same type of socket was't being used. 2) Both had the same ID number, with -3 at the end (made in Taiwan). Which, from a search, is the better 6502 to have. One was sub-labeled 8313 and the other 8323, year/mo date codes I'd presume. 3) Just saw this one. From one jiggle at one point (the ground wire came loose, yay) I could tell that was a problem with the three-wire setup. Noting all the "fun" with crimping and then soldering the little things on, next time I'll replace the socket with wires directly. Continuity was correct since inverse/Reset brought up the menu accordingly, and was the one time I squealed with joy... I recall the middle wire got nicked loose and I saw the screen flicker and sieze up too. So that is a biggie. Will just use wires and solder directly when the time comes. The vendor website states not to contact them since there are a lot of variables involved, including (paraphrased) fun with the soldering iron and possible mobo damage. Given their website also recommends installing Rapidus as a standalone and the unit without the Ultimate 1MB expansion or other goodies and I dived in to try it on has RamboXL on it anyway, I'll try again using a stock XL - by then I'll have a proper desoldering gun since my spare unit lacks sockets... which might be a good thing in retrospect as I'll solder in the Rapidus directly or find an appropriate socket.
  2. Wasn't sure if to create a new thread or revive this one. My bad :blush: Possibly. I have two units and haven't yet tested the other one yet, but have had fun problems when Rapidus starts in 65C816 mode in my 800XL -- after a delay, it goes into memory self-test and randomly fails ROM and RAM tests; each reboot is guaranteed to show different self-test failures - like both ROM segments being green or one red or both red depending on the power off/wait 10 seconds and show my hamster how to dance/power back on again. In 6502 mode everything runs smoothly. Regardless of CPU mode, in my 800XL, it will not run cartridges as it freezes instantly on powering up. Which is a tad depressing, was hoping to get Flight Simn II and Rescue on Fractalus zooming along... pretty sure I didn't fry the motherboard with the soldering iron... But the 800XL I am testing on is revison 1A and has a RamboXL RAM expansion on it. I should try setting up the Rapidus on my vanilla 800XL and see if it still acts bonkers.
  3. Do you know the technical term for the connector at CON3? (lower-right, white, 3-pin) It looks similar to a JST connector but not quite... (I have a second Rapidus I want to install in my other XL, which didn't come with the extra cables so I'm doing custom rigging and would rather get a proper connector than to solder...) Thank you much!
  4. It's an ingenious design, though I was hoping... the seller clearly got out of an XE model. They're not able to break up kits, which is understandable. Very fast support, which was awesome... I'll be ordering the full kit shortly. Testing with the case open, the Rapidus did boot so that's a big hurdle. Does the Rapidus have an external selector switch? I saw a few connectors, with CON3 looking like a switch could fit in it but am unsure. It's possible the Rapidus is running in "6502C" mode right now and not with the accelerated CPU. Not that I'm itching to test "Rescue on Fractalus" at high speed... even via passthru, if there was a problem, there'd be some anomaly so I'm fairly sure the device works fully but want to double-check as much as possible... Thanks!
  5. K. I'll check 'em out. Out of curiosity, why is it required? The layout of the 800XL makes direct placement impossible?
  6. If nothing else, and this seems more a side note, I'd recommend to get heatsinks on the chips. Electromigration and general aging causes them to get nice and piping hot, which will reduce their lifespan or cause random problems. More rapid airflow will extend their lives. Jay Miner will be happy. The aluminium RF shield is also moot nowadays, since those frequencies aren't in use anymore and your roommate watching whatever in the other room won't see interference from the computer at the time. Keep the shield removed for improved air flow too.
  7. LOL! Definitely the Atari Indus GT model. I live not in Louisiana bit a bit northward. But south of Canada. 😁
  8. Hi! I bought a Rapidus from an online auction site. The unit looks like the one pictured with the white background ("rapxe"), the top photo. After finding the Rapidus website, their documentation shows two versions of the board - the other includes a secondary board called "Adaptus", which is used on the 800XL. See the bottom photo for this, though its configuration looks nothing like the unit I won. Will the Rapidus (rapxe) require the extra board and ribbon cable? Thanks!
  9. Thanks! I will check him out if I run out of options... of which I'm down to one... Rereading the manual, the voltages for the brick they discuss are all in line... (phew) I did some further checking: The multimeter, in diode mode, shows 561 when I attach the leads. Swapping them, I get ~1100 that slows and stops at 1000. I'll retest later, I forgot to discharge the capacitors beforehand. But I also tested in resister mode, "1" is displayed regardless of which side I attach the wires. It's possible there's a shorted capacitor and I haven't yet removed said diode... Using the manual's test involving hooking leads to J7 pins 1 and 2, I get 0 volts - the manual states that 0v here means it's a bad WART. I took a close-up photo of the diode - when zooming in, it looks like it cracked right down the middle? It looks slightly askew too... I'll remove it later this week and re-test it in isolation. . I'll find where R12 is and take a snapshot of that to see if it visibly looks damaged. Or better yet, test it for resistance. If nothing else, the diode is a definite culprit. If someone did swap power connectors with an AC unit, the caps could be toast as well. possibly R12, even if it looks pristine. The VRs both had readouts that didn't seem suspicious so that might be okay. I'll swap the diode first and then do followup multimeter readouts; with luck it's just the diode...
  10. Howdy! I'm looking for an Indus GT, if one has any for sale please let me know. Thanks!
  11. Not yet. I will be procuring a ESR tester shortly; I did some quick research and that's the only way to do it? (Directly attaching the leads gave me the same 0.85v result as when testing the VREs... either way, it looks like I'll need to get one.) A short would prevent proper voltage being output at the VREs too... (I'm a bit green on this, think "Kermit the frog drunk on a cruise ship" sort of green...) As I sit here, it really sounds like it'd be worth the time to replace the caps either way... Great idea about stable reading without load. Given some of the goofy readings I'd gotten, what you said fits the theory. Your mentioning capacitors as well - noting I have other equipment using the same uf rated capacitors, I should just order what I need along with the meter. It's not going to hurt either way. Will order the caps (a shame Radio Shack isn't around any longer) and meter; fingers crossed that the caps are the sole problem. Sounds like it might be.
  12. One more update: I re-checked the PSU: it hovered around 12.25V and more consistenty. Not once after 2 minutes did it go above 13v. I started checking the VREs. I should be expecting 5~7v, I get 0.85v on both of them. Checking voltage at the DC input itself on the board, it also reads 0.85v (which is not surprising). Re-checking the PSU at the pliug after removing it from the board reads 12.2V. I'll try to check a cap after removing it from the board next. I'm not optimistic. With luck it won't read "0"...
  13. I finally got the unit disassembled. The sticker on the back holding in the board despite bending slightly the metal rear plate back, grr... Drive belt seems reasonably taut considering its age. Regardless, I should replace it. Like a rubber binder that's been out for decades and dried up, the belt will snap one day. The WART board looks pristine. None of the chips were loose in their sockets... I might reseat them later, anyway. ROM is v1.1. I'll order the newer version for this model if I can get this to power up. Without powering up the unit but to check key areas, I couldn't find a short - so far, so good, I guess. Ground was consistent to the VRMs (VREs?), as well as the voltage input. All of the capacitors look fine, no sign of bulging or anything - which doesn't mean they're not bad. I may as well replace those outright... my gut feeling is that the 4700uf one is toast. I should probably get an ESR meter too... I'll power on and test voltages later, after today's coffee buzz wears off and re-reading the schematics so I don't fry anything, I'll try to get a reading from the VREs to confirm 5v and 12v output. I'll re-check the PSU first... If nothing else and assuming the actual chips aren't damaged from (whatever caused the drive to not power up from the PSU), at least I've got spare parts of which most are likely useful.
  14. Fun side note: I had an XM301. Back when 300 baud inside a gray brick with angled power light was cool... The XM301 also had a nice little design flaw where, in some units, there were several bare wires inside the chassis by the SIO cable entry point that could short out the entire unit. Oops. I opened mine back in the day and thankfully there were no exposed wires. The solution for those who had the issue was to clip off the bare copper or wrap them in electrical tape. The only things that are good fried are few, and none of those contain electronics.
  15. Much thanks for that!! They really did a nice job with content and layout. The transformer did go above 13.0 in testing at one point, so I'm certain it's bad. I suspect the WART board might need to be replaced as well... I'll try reseating the chips once I get the unit stripped down to that level. Assuming the PSU itself isn't wonky enough to fry the WART board, I wonder if the previous owner swapped DC and AC on the drive; the manual specifying not to do that because doing so by accident would render the drive inoperable... a shame; if the Nintendo NES from a handful of years later could use AC or DC bricks so it was capable of converting an incompatible electricity type. then why not other hardware to foolproof it when they use standard off-the-shelf cylindrical connectors... I'd bet real money that's what happened with the Indus. Hmmm, I may have misread the label on the meter. (and how to read; the meter isn't going to be drawing much from the PSU now that I'm thinking about it...) Given that I did see the voltage crawl up to 15.x then go down again, it is definitely wonky. Much thanks! I'll do that tomorrow after I get out the WART board; the only way to test the capacitors is to remove them (I'll check for a short first, then start removing them to see which one(s) are bad... or I'll pick up an ESR circuit tester and get around desoldering...) With luck it'd be that simple, just a short or bad capacitor... but I'll check the VRM outputs first to verify output voltage, one component at a time... If the manual indicated not to use AC and the former owner had accidentally plugged in the wrong adapter, checking that might be a moot point but it's worth a try. (Or they were trying to get around the technical reasons. But from what little I know and read, there'd surely be some form of scorching or visible somewhere... once I remove the drive section and the WART is fully visible any issues should be easier to spot. AC into a DC device without any internal conversion would be bad news for sure... that schematic shows a diode, but clearly AC can flow to any number of components and those would be fried, generally with visible signs of damage... maybe it is a short. AC would fry any of those capacitors, if nothing else deeper beyond that point. I'm just hoping the ICs themselves are okay, if nothing else...) Thanks for the explanation on the VRMs as well!
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