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areeve

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  1. Thanks hofster for guiding me to Ray's guide. I ended up removing the CD4066 and 74LS04 and adding sockets to make future maintenance easier. The 74LS04 tested as good so I kept that, but the CD4066 was defective. After doing that and verifying by swapping the bad one and a good one and seeing the difference I now had another problem... the characters were scrambled albeit in a mapped manner meaning every space was now a @, and * was J and so forth with some also being correct such as B was still B. Before all the characters mapped correctly... just the colors were off. I ended up getting a Penultimate+ cartridge for its Diagnostic tools (as I had planned to get one anyways once I had a working VIC 20) and then the machine starting booting to just a black screen... and then it magically started working. The Penultimate+ cartridge Diagnostic software verified the memory and ROMs as all fully functional. I'm a bit puzzled about all of this and it was consistent for many power cycles so how it just cleaned itself up is a ?. I can only wonder if when I was testing and I had the board just sitting in the plastic case vs on the paper/metal shield if it was in contact with something, but that seems farfetched. Anyhow, it's all back together now and fully functional. Yay! On to the next project...
  2. I broke out my VIC-20 for the first time as I work through testing out my collection and boot up looks odd to me (picture attached from my phone camera). As you can see the characters are interspersed with blue and red ones and they should be all the same color (preferably blue characters on a white background). It's seemingly random as to what color a given character will be (e.g. whether a character is blue or red varies every time I start the system). I was hoping someone with more VIC-20 knowledge that I have might be able to suggest what might be wrong. My inclination is video memory, but it'd be nice to get a second (more knowledgeable) opinion. - Thanks, Alan P.S. It was having problems in that sometimes it wouldn't boot (just a black screen), but after a recap that seems to be resolved.
  3. I have an Atari ROM cartridge that does not work (Thunderground from SEGA). After a cleaning my next step is to check all the contacts and then the ROM chip. So far everything checks out. It has a 2732 EPROM in it, but oddly it has no circuitry to invert the chip select. I have double checked the EPROM using another cartridge with the CS inverted and that worked too. My questions... a) Can I not just tie A12 to ground for the chip select to be active? b) If not then this seems like it could never have worked? The board has notches that fit the case perfectly and I got this cartridge like 20 years ago before there would have been any real reason to counterfeit... any ideas? Thanks in advance for any help.
  4. Just to be clear, that was not the issue and was actually why this is so confusing. Getting the proper boot.rom is what allowed me to get a directory (catalog) of files in Disk Manager and load/save BASIC programs in TI BASIC in the first place. That made it seem like I had what was needed to support loading everything from disk so I figured I could load the EA ROM and then load EA 3/5 programs... apparently not. Apparently I needed an EA ROM with disk controller support in it. I'm still trying to learn about the TI's funky architecture and hopefully one day I'll pull my TI and PEB out and experiment with them (and hopefully they'll still work ?). Thanks against to those that guided me through resolving this issue. I doubt I'd have figured it out solo any time soon.
  5. Thank you! That was my issue and lack of understanding (well, still don't really understand the why, but I'll have to read up on that). It's so nice to see disk loading working here. (And thanks for responding before I spent time setting up a new MiSTer install for no reason!)
  6. I *thought* having the disk controller meant I needed the boot rom with disk.bin in it. Can you clarify what 'loading the EA with the disk controller image' means in more of a step by step? I am currently 1) Select the TI core 2) From the OSD choose load full ROM to load the EA ROM 3) From the OSD select a .dsk image for drive 1 4) Select 2 from the TI menu to run the EA 5) Select option 3 or 5 from the EA menu to run a program from the disk If I'm missing a step (or two or three...) I'd be grateful if you could share specifically what I need to do for said step(s).
  7. I tried images from the MegaPack and get the same result.... error 0 when I try to load them from the EA ROM. I am using ROMs from the MegaPack for EA, XB... etc so I have to think those are good (I questioned whether perhaps I had a bad ROM for the EA?). In addition to not being able to load EA programs, XB programs fail to autoload. It would seem I can start with the Disk Manager (1, 2, or 3) and get dirs (catalogs) of as many disks as I want and I can use TI BASIC and load/save to disk just fine, but as soon as I load a full ROM such as EA, XB, or something else then disk support dies for me meaning to EA option 3/5 gives me an error 0 (and XB also does not autoload) and I have to Reset to get the little disk support I have working again. I'm pulling my hair out trying to get this to work. I even tried my other MiSTer in case it was some obscure hardware error. The only other thing I can think of is starting with a fresh SD install so that's up next.
  8. Thanks for the quick responses... yes, both images are 90k (92,160 bytes) which matches the length of my TI99dir created image. As I'm not familiar with either PC99 or theV9t9 .dsk image format I can't say for sure, but after looking at both in a hex editor the headers, at least, look similar. I've attached the two images in ? if there's any interest in looking at them. In the meantime I'll try some images from the MegaPack. - Thanks, Alan 0031-6 Atari Game [EA OPT3 Atari].dsk 0029-4 EA Games.dsk
  9. I am hoping someone can help me as I attempt to document TI floppy disk usage in the MiSTer Manual (https://github.com/adreeve/MiSTerManual/). I was able to create a blank TI disk image using TI99Dir and load/save a BASIC program created in TI BASIC, but am unable to load games from the Editor/Assembler cartridge. I have several disk images from whtech.com and I am able to get a directory of the files on the disk using the Disk Manager software, but when I try to load/run programs from said disk I get an Error 0. At that point if I return to the EA cartridge then it can no longer perform a directory function on the disk. Any ideas as to what I might be doing incorrectly? Thanks in advance.
  10. The reading isn't coming from the 7805... as above I removed that and got the same reading. The reading is coming from across the resistor that bypasses the 7805 and is high (on the schematic that is also above), apparently, because of a lack of a load... but we're getting a bit beyond my 'learner' understanding of all this. I guess it sounds like my power supply is fine, though and I need to start digging into the main board and what's going on over there.
  11. Actually I am wrong about the resistor... it's just such a low value resistor at 33 ohms this it passes the continuity test on my meter. So I guess we're saying that reading +13v on the +5v line is normal? I'm just plain puzzled by this.
  12. As I'm having issues that this thread deals with I'll throw out that the schematic appears to be labeled incorrectly... the R203 in the schematic that is discussed here is really R202 on the actual power supply board (the real R203 as labeled on the power supply board is close to the bottom middle of the schematic). After doing a 48k memory upgrade and a recap my 400 went to the familiar blue memo pad screen (just blank) and then the system died (power light went out / black screen). In diagnosing I discovered that the +5v from the 7805 was really +13v. My first suspect was the voltage regulator so I pulled that off and it's fine. I then tested the board without it and was still getting +13v on the (empty) output through hole where the 7805 was which is when I noted the resistor could be one culprit. In circuit it was a short so I pulled it to verify and it's a short alright... Thanks for the info on its purpose. I'm still not clear on why I'd expect a +13v reading from a multimeter. We're not saying that if I check the SIO +5v pin that I'd see anything other than +5v are we? My concern is what other damage might have occurred as part of this fault ?
  13. I'd like an Eclaire XL too if/when they become available again.
  14. I have a printed copy of a 1.0 version of the FAQ dated Feb 15, 1995. I'm trying to digitize everything to take less space and was looking for a digital copy... all I can find is 0.7 so I need to scan it. If you want a copy of my scan let me know.
  15. I'm in for 1 please. - Thanks, Alan
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