+videofx Posted January 2, 2023 Share Posted January 2, 2023 I have 2 questions about the 1200XL and U1MB 1. Can someone please share of photo of where they drilled their holes in the 1200XL motherboard to install the U1MB 2. Any issues with the UAV and the U1MB? Thanks! Quote Link to comment Share on other sites More sharing options...
oracle_jedi Posted January 2, 2023 Share Posted January 2, 2023 Here's mine: I used one of the existing holes in the motherboard and a single stand off. It is enough to keep the board secured. In this image you can also see the Stereo board. I think this 1200XL uses a Clear Video fix but the UAV should not cause any problems in my opinion. Good luck. 1 Quote Link to comment Share on other sites More sharing options...
Beeblebrox Posted January 2, 2023 Share Posted January 2, 2023 (edited) @videofx The only known issue with installing an U1MB in the 1200XL is that you often have to add a 100pf ceramic capacitor to the underside of the U1MB PCB itself. It's a well known and easy mod to fix instalbility/crashing, costs virtually notihing and is very quick and easy to install. The issue is almost exclusive to the 1200XL - although I always do it as standard with U1MB whatever A8 it's going into because I may as well. See here for details Also when I installed U1MB in my 1200XL I followed FJC's install video guide: Edited January 2, 2023 by Beeblebrox 1 Quote Link to comment Share on other sites More sharing options...
+slx Posted January 2, 2023 Share Posted January 2, 2023 Used a single stand-off as well. I considered printing a part but once the machine is closed nothing is going to tug on the installation anyway, unless you frequently travel very roughly. Quote Link to comment Share on other sites More sharing options...
+videofx Posted January 2, 2023 Author Share Posted January 2, 2023 8 hours ago, Beeblebrox said: @videofx The only known issue with installing an U1MB in the 1200XL is that you often have to add a 100pf ceramic capacitor to the underside of the U1MB PCB itself. It's a well known and easy mod to fix instalbility/crashing, costs virtually notihing and is very quick and easy to install. The issue is almost exclusive to the 1200XL - although I always do it as standard with U1MB whatever A8 it's going into because I may as well. See here for details Also when I installed U1MB in my 1200XL I followed FJC's install video guide: Thanks for the info! I have read a lot and seen FJC videos but nothing mentioning the cap. So that will be the first thing I do once I get the board. 1 Quote Link to comment Share on other sites More sharing options...
+videofx Posted January 2, 2023 Author Share Posted January 2, 2023 10 hours ago, oracle_jedi said: Here's mine: I used one of the existing holes in the motherboard and a single stand off. It is enough to keep the board secured. In this image you can also see the Stereo board. I think this 1200XL uses a Clear Video fix but the UAV should not cause any problems in my opinion. Good luck. Great Thanks! Then that what I will do. I will use a hole that's already there. Quote Link to comment Share on other sites More sharing options...
+videofx Posted January 2, 2023 Author Share Posted January 2, 2023 Now all I have to do is wait for my U1MB to arrive, install and flash Thanks everyone and Happy Atari New Year! Quote Link to comment Share on other sites More sharing options...
Beeblebrox Posted January 2, 2023 Share Posted January 2, 2023 (edited) Cool. Are your OS ROMs/MMU socketed to make it easier to convert? Mine were not. Are you using dual wipe or precision sockets? Edited January 2, 2023 by Beeblebrox Quote Link to comment Share on other sites More sharing options...
flashjazzcat Posted January 2, 2023 Share Posted January 2, 2023 You may or may not need the cap. When I've installed U1MB in 1200XLs here, I've found it necessary only in a handful of cases. So: try it without first (not that the cap will do any harm even if it's not needed). Quote Link to comment Share on other sites More sharing options...
_The Doctor__ Posted January 2, 2023 Share Posted January 2, 2023 Future proofing, the cap doesn't hurt, it only helps. Quote Link to comment Share on other sites More sharing options...
flashjazzcat Posted January 2, 2023 Share Posted January 2, 2023 (edited) Well, it doesn't help at all if it's not required; I'm just pointing out that not every 1200XL needs this mod. Edited January 2, 2023 by flashjazzcat Quote Link to comment Share on other sites More sharing options...
+videofx Posted January 3, 2023 Author Share Posted January 3, 2023 7 hours ago, Beeblebrox said: Cool. Are your OS ROMs/MMU socketed to make it easier to convert? Mine were not. Are you using dual wipe or precision sockets? Mine are all socketed I will use the original sockets. If I don't like the way the cable sits then I will replace them with precision sockets. Quote Link to comment Share on other sites More sharing options...
+videofx Posted January 3, 2023 Author Share Posted January 3, 2023 7 hours ago, flashjazzcat said: You may or may not need the cap. When I've installed U1MB in 1200XLs here, I've found it necessary only in a handful of cases. So: try it without first (not that the cap will do any harm even if it's not needed). Cheers! I will try it first without the caps. What are the symptoms ? Do they appear right away or do I need to wait or do something special? Quote Link to comment Share on other sites More sharing options...
+Stephen Posted January 3, 2023 Share Posted January 3, 2023 12 minutes ago, videofx said: Cheers! I will try it first without the caps. What are the symptoms ? Do they appear right away or do I need to wait or do something special? I believe it was instability on hitting the reset key. I do not recall if the issue was it could sometimes cause a coldstart when not needed, or if the reset line was just not held long enough so the system would not reset. Regardless, once installed, try hitting reset key a few times and just make sure the machine acts normal. Quote Link to comment Share on other sites More sharing options...
+videofx Posted January 3, 2023 Author Share Posted January 3, 2023 4 minutes ago, Stephen said: I believe it was instability on hitting the reset key. I do not recall if the issue was it could sometimes cause a coldstart when not needed, or if the reset line was just not held long enough so the system would not reset. Regardless, once installed, try hitting reset key a few times and just make sure the machine acts normal. Thanks I will try that! Quote Link to comment Share on other sites More sharing options...
_The Doctor__ Posted January 3, 2023 Share Posted January 3, 2023 (edited) bonus double feature... and so on, also consider the 74F08 and other stability mods, maybe some video mod clean up, the simpler ones that tweak and don't re invent the wheel. but that's just me, future proof and bullet proof so you don't have to tear it apart over and over and over again stressing the machine, it's case, etc etc. just a few seconds now vs tear down and rebuild time later, so why not. Edited January 3, 2023 by _The Doctor__ Quote Link to comment Share on other sites More sharing options...
Tillek Posted January 3, 2023 Share Posted January 3, 2023 21 hours ago, flashjazzcat said: You may or may not need the cap. When I've installed U1MB in 1200XLs here, I've found it necessary only in a handful of cases. So: try it without first (not that the cap will do any harm even if it's not needed). I didn't add anything to mine when I did it. 1 Quote Link to comment Share on other sites More sharing options...
+videofx Posted January 10, 2023 Author Share Posted January 10, 2023 OK folks, look what I just got! Time for surgery! 2 Quote Link to comment Share on other sites More sharing options...
Beeblebrox Posted January 10, 2023 Share Posted January 10, 2023 (edited) @videofx Nice. Great to hear your 1200XL is socketed although can I double check as the 1200XL comes with 2 x 24 pin OS chips so presumably the sockets you have already are oversized and thus already 28pin? If not you'll need to take the lower socket out which is the one you wil be using for the single OS mod/U1MB and replace it with a 28pin socket in readiness for the 28pin harting ribbon connector cable. Then is just the other reconfiguration of the passive components for it to accept the dual to single OS conversion as per the instructions. Also double check if the U1MB's harting ribbon cable connector has flat pins or round ones. If it has round ones and if you do need to install the 28pin socket then there is no point installing a double wipe socket. Instead install a precision round pin type. Same goes (I guess), if it turns out your harting ribbon cable connector has flat pins, where you may as well install the double wipe in that instance. Goes without saying if you do need to install a 28pin socket then you only want to do it the once. Thankfully the 1200XL's board has the extra 4 x vias on the pcb for the 28pin socket already. My 1200XL: Instructions: Edited January 10, 2023 by Beeblebrox Quote Link to comment Share on other sites More sharing options...
flashjazzcat Posted January 10, 2023 Share Posted January 10, 2023 On 1/3/2023 at 3:41 AM, _The Doctor__ said: bonus double feature... Yes: many 1200XLs require the mod, but this also infers that some don't (otherwise Bob would have used the word 'all' instead of 'many'). I opined previously that the mod 'should be routine' when it comes to 1200XL U1MB installations, but that still doesn't mean it's necessary in every case (more that I wouldn't mind wasting my time on redundant mods, although in practice I simply add the cap when it proves to be necessary), or that it does any good at all if it's not needed (as per my prior two posts). If the cap was built into the U1MB itself, it would likely do no harm, but since it takes a measurable amount of time to fit it after the fact, it's worth pointing out that it might not be needed (as Tillek seems able to vouch). Quote Link to comment Share on other sites More sharing options...
+videofx Posted January 11, 2023 Author Share Posted January 11, 2023 4 hours ago, Beeblebrox said: @videofx Nice. Great to hear your 1200XL is socketed although can I double check as the 1200XL comes with 2 x 24 pin OS chips so presumably the sockets you have already are oversized and thus already 28pin? If not you'll need to take the lower socket out which is the one you wil be using for the single OS mod/U1MB and replace it with a 28pin socket in readiness for the 28pin harting ribbon connector cable. Then is just the other reconfiguration of the passive components for it to accept the dual to single OS conversion as per the instructions. Also double check if the U1MB's harting ribbon cable connector has flat pins or round ones. If it has round ones and if you do need to install the 28pin socket then there is no point installing a double wipe socket. Instead install a precision round pin type. Same goes (I guess), if it turns out your harting ribbon cable connector has flat pins, where you may as well install the double wipe in that instance. Goes without saying if you do need to install a 28pin socket then you only want to do it the once. Thankfully the 1200XL's board has the extra 4 x vias on the pcb for the 28pin socket already. @Beeblebrox I have 28 pin sockets so nothing to do there. My U1MB cables are flat. First order of business is to remove the RF modulator since its in the way of my U1MB install. Then install the U1MB. I will do the install tomorrow. \ Quote Link to comment Share on other sites More sharing options...
Beeblebrox Posted January 11, 2023 Share Posted January 11, 2023 3 hours ago, videofx said: I have 28 pin sockets so nothing to do there. My U1MB cables are flat. First order of business is to remove the RF modulator since its in the way of my U1MB install. Then install the U1MB. I will do the install tomorrow Cool. That is good news. Yeah it's been a while but I realised my 1200XL came with the rf modulator already removed. Good luck. Quote Link to comment Share on other sites More sharing options...
+videofx Posted January 12, 2023 Author Share Posted January 12, 2023 Install complete. i have 2 problems 1. It wont boot a cartridge or my fujinet it always goes to self test as shown in the photo 2 RESET-HELP takes me to the firmware. And I can do everything and save and the quit and takes me to self test and wont boot cartridge or disk no matter what settings I choose in the firmware. I have tried all permutations. Please help Quote Link to comment Share on other sites More sharing options...
+videofx Posted January 12, 2023 Author Share Posted January 12, 2023 I need to boot the fujinet so I can install FJC’s firmware from his firmware.atr I have checked all my connections many times and they are correct. Top of W6 to Pin 23 CPU If necessary I will show the photos of all the connections THanks! Quote Link to comment Share on other sites More sharing options...
Beeblebrox Posted January 12, 2023 Share Posted January 12, 2023 @videofx Quote Link to comment Share on other sites More sharing options...
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