Jump to content
Have You Played Atari Today?
2600|5200|7800|Lynx|Jaguar|Forums|Store  

BigO

Members
 View Profile  See their activity

  • Content Count

    4,669

  • Joined

  • Last visited

Posts posted by BigO

  2. Posted · Edited by BigO

    On 3/23/2021 at 1:31 AM, Rik1138 said:

    Their information is wrong...  The Microvision system was $40 in 1979-1980, and the cartridges were about $16

    So adjusting for inflation, it's about $127, and the carts would be $51.

    Sheesh. No wonder I didn't have one back when I was free-school-lunch eating, poor rural kid.

     

    That would have been multiple summers' worth of picking and selling wild blackberries and "pop bottle hunting".

     

    I have three of these things now. I have arrived!

    • Like 1

  3. Posted · Edited by BigO
    Typo

    On 3/19/2021 at 5:30 PM, Atariuser85 said:

    I tried the paper, but that did not fix the problem. Actually lost pixels.  But, thank you for the suggestion anyway, sounded like a great idea.  However, by reassembling the unit I now have the bottom row of the pixels.   I am now missing the top row but I can now see the breakout paddle.  I notice the knob (potentiometer) is a little rough to move.  I have 3m silicon spray, should I spray that into the potentiometer or will that short it out?  How do I clean / provide maintenance to the potentiometer?  I don't have anything else besides 3M Silicon spray.  Thanks

    I had a lot of mechanical drag and roughness in the paddle control on one unit. It was due to wear and crud between the knob and the other piece of plastic that the knob passes through. Cleaned the area and applied a very light coat of silicone grease to fix the issue. I've seen at least one other person post the same issue. 

    • Like 1

  4. Posted · Edited by BigO

    On 3/9/2021 at 2:41 PM, nickle241 said:

    it actually wouldnt matter from what i can tell, the screen is just a matrix and both edges are the same with the traces on the 'inner' layer, it would take one hell of a manufacturing screw up for the screen to be outright defective in that way, my old one leaked in such a way it made it easier to see the internal traces and there is nothing complex about it that would care if it were reversed

    That isn't what I meant.

     

    I know it's a matrix. I'm talking about which face of the glass the zebra strip is contacting, not the polarity of the connection. I should have used the term face instead of side, I suppose. 

     

    (As a matter of trivia, according to my research, the polarity of the connection is reversed frequently under normal operating conditions to prevent damage to the display. There's a specific pattern/timing fed from the processor to the controller that causes the controller to reverse the polarity of the signals.)

     

    If the reflective material were attached to the wrong surface, then the conductive traces would be on the top faces of the pads instead of the bottom side when the LCD is installed with the reflective surface down. I think the symmetry would let that happen. I don't have one of the LCD's in front of me at the moment.

     

    Again, it's a very unlikely scenario. But, it's not expensive to check.

  5. Posted

    3 hours ago, Deteacher said:

    Ok, I checked every trace on the board for R0-R15 and C0-C15 to the chip and there's continuity on each line.  So, the only thing I can deduce now is I'm simply not lining up the zebra connectors properly.  But I would think I'd be getting, at the very least, garbled graphics, like livingonwheels was getting.

     

    One pixel...my kingdom for one pixel!  :(

    A really dumb, far-fetched, out-of-left-field question: did they assemble the LCD backwards, with the reflective surface stuck on what should be the front? If that were the case, I believe the symmetry of the display would allow it to be physically installed. It's pretty hard to see those transparent conductive traces, but held in the light a certain way and watching the parallax as you move the display does let you see which side they're on (at least on one of the OEM displays that I de-installed and other bare glass LCD's I've tinkered with).

    However, if 5-11 tested every unit, then this unlikely scenario would be rendered un-possible.

  7. Posted · Edited by BigO

    7 hours ago, Deteacher said:

    While I patiently wait for my screen to arrive, I have a question about the potentiometer.  I have no idea if it's good or bad, yet, but let's assume that it is.  Would a potentiometer from an Atari 2600 paddle work in it's place?  Are they one and the same?  Sorry if this is a noob question.  

    No, the one in the Atari paddle is 1,000,000 ohms The one in the Microvision is 10,000 ohms. 

    Okay, technically it would electrically function and wouldn't hurt anything. But for every degree of rotation you would get 1000 times the movement that you would get with the original. It would be unplayable.

     

    The pot in the Microvision is probably okay, or salvageable by cleaning. I use Deoxit that is made for cleaning and lubricating potentiometers.

    • Like 2

  9. Posted · Edited by BigO

    https://www.amazon.com/Analog-NTSC-Tuner-Demodulator-Output/dp/B01KC03BQ2/

     

    Not an endorsement of this unit, but I have a much older analog "demodulator" that works great. Connecting it between my 2600 and Sharp Aquos 60" composite input yielded *a lot* less lag than connecting the 2600 to the NTSC tuner in the TV. I think mine may have been made by RCA.

    Using the TV's tuner, I was completely unable to play Circus and Kaboom due to the lag. Using my external "demodulator" (because it sounds more important than "tuner") hooked up to the TV's composite input I was able to play both games. Still some visible lag, but much better than the direct option.

    • Like 2

  10. Posted · Edited by BigO

    It  seems like, according to my email notifications, I miss everything. I've been in a couple of times and there was no visible activity. But I get emails that tell me what i missed.

     

    Then i read the emails of disjointed pieces of conversations and realize I'm still not missing anything.

     

    Gotta figure out how to shut down those emails so I don't know about what I'm not missing.

    • Like 2

  12. Posted

    Just stumbled across this old post while looking for something else. Since the OP didn't report back, I thought I'd comment with my experience for anyone looking at this down the road. 

     

    The outputs of the 4538's would be equivalent signals to what trackball joystick emulators use as joystick signals. I tried to pick these signals off to add joystick emulation capability to a CX53 enhancement kit I built years ago.

     

    The attempt was essentially a failure. The retriggerable one-shot configuration results in a minimum pulse width that is too short compared to a typical JS emulator, so the movement is choppy and you have to spin the ball really fast to get it to steady out. If you want a workout, it might be fine. Otherwise, you'd have to change the RC timing component values in the circuit to get it to behave as a workable joystick emulator. If I recall correctly, I looked into externally paralleling in some components to change the timing and I found that I'd have to actually break into the circuitry. As I was going for easily reversible, no-solder adaptation, I bailed on that idea. (I don't like playing JS games with a trackball anyway).

     

     

  16. Posted

    Nice.

     

    I also worked on a Barrage game for Microvision. I did mine with a little PIC uController using assembly language. I'm not sure I could bring myself to use a real processor for this.

     

    I got as far as generating the falling objects, controlling the catcher (paddle control) and tracking the score. In my mind I was writing a Kaboom! clone.

     

    It was fun reverse engineering the LCD controller protocol, figuring out the paddle reading, and making the speaker chirp.

     

    Level shifting was still hacked up.

     

    Having solved what I felt were the fundamental problems, I set it aside and never went back to it.

     

    If I were forced to come up with a "commercial" product for the Microvision now, that's where I might employ a real processor. My focus would be a "universal cartridge" to eliminate the need to produce that huge cartridge enclosure toward the end of supporting new game development.

     

    Some sort of plug in slot would allow memory of some flavor, carrying the game, to be plugged in. It would be really nice to insulate game developers from having to deal with the intricacies and quirks of the OEM LCD communication.

     

    Likely, the market, so to speak, would end up calling for a flash cart loaded via USB. That's cool but I like the game-per-cartridge retro vibe, too.

     

    Unlike when I originally was tinkering in this arena, the reality of the replacement screen project(s) means there might be a meaningful community interest in goofy projects like this.

     

    Given real life, I won't do any of this. But I would follow with interest anyone who did work up something like this.

     

     

    • Like 1

  18. Posted · Edited by BigO

    On 11/29/2020 at 8:13 AM, e5frog said:

    It would be really cool having a "Channel  SD" cart. There are people with finished solutions, that they aren't keen on sharing (I understand why), selling something like 20 carts a year is perhaps not a market that is tempting to spend time on. Unless you're into the system yourself. ;)

     

    I have been meaning to make  a simple dev cart for years that is able to load data via USB and not having to use an eprom programmer and socketed memory... hasn't happened yet even though CAD drawings have been done for several versions. It's mainly a "money for prototyping" problem, which has been tight for the last six years with the wife in school (for adult people). 

     

    There's a system for Vectrex identifying a 39SFxxx flashrom as a USB memory which seems interesting.

    Instead of the programmer as a separate part it could be built into the cartridge and you'd have a USB connector in the cart.

    Borrowed one of them from a friend but haven't had time to spend on it yet. 

    SD would be really cool though but seems to have a larger threshold. 

    Interesting idea. If I had sufficient ambition to make something like this, I would consider EEPROM instead of flash. While doing development work, it might be a cool feature to be able to just poke a new value in a single "ROM" location in a straightforward manner. 

     

    Also, it seems like the EEPROM would be more directly analogous to the original ROM chip (of which I know very little) so might simplify the interface to the console.

     

    Being simple myself, I gravitate toward simple. Often, that makes things more complicated. :)

     

  19. Posted · Edited by BigO

    On 10/25/2020 at 4:12 PM, joeatari1 said:

    I have sort of shaky hands too.  Stupid genetics and all.  I also have a herniated disc and a bone spur in my neck both pushing on my spinal column a little.  Don't need surgery yet but it's coming.  I find the better I magnify things and concentrate, the easier it is.  Glasses and a good magnifier with a lamp.

    Bummer. I had an unpleasant experience with that condition. Discectomy with fusion:C4-C5-C6 fixed me right up. Nerve pain and dysfunction were gone when I woke up from surgery.

     

    My unsolicited advice is as soon as you need the surgery, get the surgery.

    • Like 1

  20. Posted

    28 minutes ago, thevnaguy said:

    Towards the beginning of the thread (and throughout the thread) many have been posting how many they would be in for, would this would be a good measure of quantities?   Why not get a list together of those that will definitely buy one, two, three, etc...?  I for one want three :)

    I wonder if the forums polling feature would be a reasonably manageable way to gather such "interest check/quantity" information.

     

    It would be less painful than reading every post and tabulating. Probably kinda too late for this topic.

  23. Posted

    If you have any fabrication skills, off the shelf parts could be used to build yourself a controller: 
    https://www.amazon.com/Tegg-Tactile-Phone-Style-Arduino-Raspberry/dp/B07RY85MGF/ref=sr_1_2

    https://www.adafruit.com/product/480

     

    It should be possible, though potentially somewhat tedious, for someone to guide you through the wiring remotely.

    If you should undertake that, it would be best to start a new thread. I'm sure I've polluted this one enough as it is.

  24. Posted · Edited by BigO

    Not sure it's an exact match, but pretty sure that this one I have in my parts bin would fit. Those tabs might be in the way. It looks like the original connector has the tabs completely outside of the pins, where the ones I have overlap the outer two pin holes a bit. Some whittling might be called for. :)

    So, yeah, it's probably common enough not to consider the connector a limiting factor.

    I bought the same connector (with more positions) for a controller project a few years ago.

     

    1067580340_WIN_20201010_07_54_10_Pro(2).thumb.jpg.dec0a8c7a2eae5e4861bc82235944fbc.jpg

     

     

    In looking again, I noticed that the schematic doesn't supply any pin numbers for the controller connections. So, somebody building a controller would need to trace the connector pins back to the PIA or figure out the pins via trial and error. Most likely, the Rows would be grouped together and the Columns would be grouped together on the connector which would make the guesswork less random. Either way, one would need a console at hand to come up with a working controller.

    Also, if it's the "main" controller that's broken and preventing you from playing games, I see no electrical reason that you couldn't just swap the connectors where they plug into the main board. The label on the controller would be wrong, but surely you could manage to compensate for that in some manner. :) I don't think it would do any damage to plug the connector in backward anyway so strict keying shouldn't be necessary.

     

    WIN_20201010_07_54_10_Pro.jpg

  25. Posted

    2 hours ago, Judge Mental said:

    It's one of those white plastic heads with pin holes that slip onto these metal pin thingies that come out of the board. 

    Heh, that narrows it down to about 99% of the connectors in the world.

    Actually, I was thinking of a picture. Surely you must carry pictures of the innards of all of your consoles with you wherever you go. :)

AtariAge
Forums
Store
General
Follow AtariAge

Copyright ©1998-2021 AtariAge

×
×
  • Create New...