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Stephen Moss

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About Stephen Moss

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    Stargunner
  • Birthday 12/20/1970

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    Cambridge, United Kingdom
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    American Football, Golf, Electronics, Programming, Sci-Fi, Indoor Climbing

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  1. Nice collection. Unfortunately, even in the best of times it is unlikely most people have 10K floating around with which it buy the entire collection, in the current situation where finances have become tight for many it is an even tougher ask. If you do have to break it up you could save some listing time be selling in bundles rather than listing everything individually, i.e. Small companies that only made a few carts (i.e. Mystique) sell as a bundle by producer Others perhaps bundle by genera and alphabetically by title, i.e. Arcade A to G, Arcade H to T to create smaller and thus more affordable bundles List the consoles and any extra controllers individually List very rare/unique items individually That way any interested parties can mix and match consoles, controllers and game bundle to suit their preference and budget.
  2. Those TDA7073 are the drive chips for the CD Motor, Focus & Tracking and are powered with 7V from the incoming external 9V supply, which is sub regulated down to 5V by U13 and 7V by U5, bot hare LM2941's Pin 3 = GND, p9n 4 = Vin, Pin 5 = Vout. The capacitors you referred to are across the In+ and In- pins, of the devices, with the power off it is possible a low resistance might be a normal reading. Either way if they are shorted that may stop the CD motor and head moving and thus the disc not being read but I would think that would then be more likely to result in some kind or error message (no disc?) being displayed rather than a blank screen, and be unlikely to interfere with the detection and playing of an inserted game cart. However, I believe that Butch (U9) is powered directly from the 5V line coming from the Jaguar via the cartridge port and I would assume that Butch is either responsible for running the CD unit BIOS itself or loading it into the Jag (more likely the former). Consequently, and I may be wrong, but even if the aforementioned drive IC's are shorting the power I don't think that should affect Butch beyond it displaying the power message. If the CD unit is that dead in the water your most likely causes are probably going to be... 1) Complete loss of power 2) Screwed up BIOS so it just is not doing what it should and getting totally messed up or 3) A Problem with Butch as that is essentially responsible for running the whole CD unit. You mentioned installing a new BIOS, which I believe would be in U10, if we assume the BIOS installation was good then the fact that the Jag does nothing (assuming it is working without the CD unit) would lead me to look at Butch first, whether Butch runs the CD BIOS or is responsible for loading it into the Jag something has to tell the Jag there is no power to display the power message or some CD unit related boot screen. The complete lack of responsiveness and the non running of a game cart (possibly Butch not detecting it and thus freeing the bus to act as a straight pass through) is all making me think Butch is likely to the problem. Consequently, I suggest checking every GND and 5V pin has continuity and the correct voltage, plus the voltages on the clock and reset pins. There is no clear indication as to the correct status of the resets but normally the are active low (0v) for reset.
  3. If you insert a cartridge in to the the CD unit, does that run either with or without a power source connected to the CD unit? Do all the CD/HD jumpers present and in the correct position?
  4. That is why they are so popular, although I would be cautious about always relying on the USB power as the primary power source. Yes, it is convenient particularly while the Ardiuno is connected to a PC (which is why people do it) but if the USB bus voltage is out of spec, i.e 4.2v instead of 5V it can cause problems. For example if you are reading an analogue input from a source that has a separate supply your ADC results will be off as the maximum ADC value is now relative to 4.2V not 5V, and any conversion calculations using the ADC value would be based upon it being relative to 5V hence the resulting error. I have run into that problem before, although it depends on the end application as to whether to not USB bus undervoltage is likely to be an issue . Also, be aware their IDE can, under certain circumstances, actively prevent you from using the full functionality of some of the Microcontrollers peripherals which is a big no-no for me. They should not be restricting use of the Microcontroller device like that (particularly when undocumented) as it leads to days of frustration trying to figure out why perfectly good code is not producing the expected result.
  5. As Danjovic stated adding a capacitor, could mess up the timing and therefore the positioning. I would forget the conversation you linked to as... a) It is talking about connecting to the ADC input of a microcontroller and you cannot be certain of the circuitry being used b) It is referring to creating a potential divider with another resistor which is the wrong way to do it anyway c) The individual instigating the thread clearly indicates they do not know how the controllers work in the Atari and it would appear neither of the respondents know how to do it correctly either as they are all looking at it as a variable voltage and not a variable current. In the Atari and old PC Game port controllers a potentiometer is used as a variable resistor with one end connected to 5V and the other end to the input pin. On the other side of the input pin will be a capacitor to ground and possible a fixed resistor between the input pin and the capacitor. As the potentiometer is turned its resistance changes and thus the amount of current flowing through it into the capacitor changes. To read its position the capacitor is discharged, and then allowed to charge, either the voltage across the capacitor is read after a fixed time period, or the voltage across the capacitor reaches a point where it triggers an interrupt and a timer is read. Either way Timer value or ADC result give you a digital value that represents the position of the potentiometers wiper that in turn determines the screen position of the players object. In most cases there will always be some small variation in the resulting value even if the potentiometer is not moved, commonly referred to as quantization errors, which could be down to minor changes in timing (one or two clock pulses difference in when the reading is taken) or electronic noise pickup. Sometimes those changes are too small or infrequent to notice, where they do become noticeable there are strategies to combat that, for example with an ADC one could set or clear the two least significant bits of an 8 bit result which will be the ones to fluctuate or rotate a 10 bit result to the right twice which does the same thing. Another method is oversampling, where you read the input say 10 times and then use the average value as your position value. I suspect the heart of whatever you are using is one of these god awful Arduios which makes anyone think they can be an electronics wizard and come up with the next "great" piece of wholly pointless IOT junk. Consequently, in the majority of cases the code is written by people who know little if anything about programming in general, programming micrcontrollers or electronics and who have probably just cobbled something together by copying and pasting code and libraries written by other people who also don't really know how to code and you end up with something that kind of works but often not as well or as efficiently as it could. I suspect that whatever you are using may not have had any quantization correction included and just basic code to read an ADC input was used or it has not been screened to eliminate noise pickup, hence the jittering
  6. I think I have a solution, the 4016BE on resistance it a little high, it will probably be OK but you might have to increase the resistor values from 4K7 to 5K6 just to ensure the voltage drops low enough to turn the switches off. I recommend using the 74HC4016 instead if you can get it as it has a much lower on resistance. I am assuming your pin 8 to 9 comment means that as the Amiga is essentially an ST clone the controller inputs are the same and are active low (think I forgot to tie the mouse and Coleco grounds together in the diagram). So with the Enable pins being active high we need to invert the pull to ground to a pull to 5V which is what U1b and U1d do (you might want to change which switch does what for a better PCB layout), I will describe how relative to U1b... When the Right mouse button is not pressed the the Enable pin (E) is pulled high via R4 turning the switch on and connecting the bottom end of R5 to ground, turning U1c off. When the Right mouse button is pressed it pulls the Enable pin to ground, the bottom end of R5 is not longer connected to ground and pulls the Enable pin of U1c high connecting Coleco controller port pins 6 to 8 - making the right mouse button Fire 1. The left mouse button works similarly connecting Coleco pins 5 & 6 (U1a), making it Fire 2. It is also connected to the bottom end of R5 which pulls it to ground, turning off U1C preventing 6 & 5 also being connected to 8. So... Right Mouse Button only = Fire 1 (Coleco port pins 6 & 8 connected) Left Mouse Button only = Fire 2 (Coleco port pins 5 & 6 connected) Both Mouse button pressed at the same time = Fire 2 (Coleco port pins 5 & 6 connected) Well at least theoretically, if both mouse buttons are pressed virtually simultaneously, the speed with which the switches react could result in brief period where Coleco pins 5, 6 & 8 are connected together. To prevent that you would have to add some form of timing/synchronisation circuitry. Personally I would use an 8 pin PIC, they are small, cheap and you can program in any delay time you want within reason. You may notice R3 is missing, I had it in I but removed it as I no longer needed it.
  7. Don't worry about the delay, the all that other things that take precedence from time to time. Measure the voltage on pin 10, 11, 12 & 13 of U6, from earlier test think you will read 0, 9, 9, 0 respectively, if that is the case what does it read after you have shorted pin 7 & 11 of U6 for a couple of second and removed the short? If you still read 0, 9 ,9, 0 and have a second person with a steady hand available (or can solder in the pin 7-11 short what voltages do you get on those pins with the short in place? Also measure the voltage between pins 10 & 13 (one meter lead on each). Would still be helpful to also know... What is the voltage measurement across (one meter probe each end) D11 (top edge, left of VR1) and C52 (below U6). What is the voltage across either D12, C44 or R75 (below VR1 and right of TP19)? With all power sources disconnected what is the resistance measurement across the Source (indicated on PCB and Drain (large tab on bottom edge) of Q12, make the measurement with the meter leads connected in both directions.
  8. If you have paddles and no specific replacement part is suggested then take them apart and measure the body size and shaft mounting hole diameter. As far as I know they use fairly standard pots so body will be about 12mm dimeter by 5 mm and have a 6.25mm (1/4") diameter threaded mount. Type is panel mount as opposed to through hole (PCB) or surface mount (SMT), you already appear to know the required resistance and track type. Power requirement will be low as 5V @ 1MOhm = 25uW, at 1Mohm resistance anything that physically fits should have a high enough power rating. If no specific replacement switch suggested, finding one that fits exactly in place of the old one may be more difficult, but the type will be a single pole single throw (SPST) momentary (non latching). Again you can take the general body size of the original as a guide to make sure it will fit inside the controller but the length and diameter of the actuator will be fairly critical, too wide to fit in the cap and filing it down could be a pain, too thin, at least you may be able to wrap it in tape to bulk it out a little but it may be hard to get it the cap. Too long and you may be able to cut it to length, too short and it may never actuate.
  9. It is not exactly clear what you want as... You have two sixes and two eights, first is it unclear if they are the same 6 & 8 or different pairs 6 & 8 and whether or not they refer to controller cable pin, console port pins or the 74HC4053 pins. The in one image connection are label A and the other B. Perhaps if you just called you connection point A, B, C, D or 1 , 2, 3, & 4 and then indicates the different options you wanted in may be easier to under stand what you want, i.e. Option 1) 1 connected to 2 Option 2) 1 connected to 4 Option 3) 3 connected to 1 & 4 Depending on what exactly it is you want the CD74HC4053 may not be the best device is the device you want as it is more or a multiplexer than a switch, the CD4016BE may be better.
  10. The first issue is that the direction pins are pulled high internally by a transistor (usually, I think the tech is too old for LASER trimmed resistors) inside the RIOT so the junction resistance and therefore current handling capabilities and resulting LED intensity is unknown. With the switches pulling the input pins to ground it would seem unlikely that simply by placing an LED in there you would draw enough current to do any damage as it can handle the joysticks short to ground input method. However, two possible ways it may have caused damage are... a) You were connecting the LEDs in a way that when multiple inputs were active it resulted in driving the inputs directly from the 5V resulting in excess current input that caused something to burn out or b) Wiring the LEDs directly in series with the joystick switches was not a good concept in general as a standard LED typically requires a voltage drop of 1.8V, consequently a direction or fire button input voltage was likely to be sitting at around 1.8V (if the LED conducts) and not 0V. 1.8V is in the forbidden voltage range for a logic input and so you may find that detection of the Joystick inputs is not consistent as it randomly determines if it is a logic high or logic low. Additionally, an input voltage outside of the forbidden range correctly results in some transistors on and others off, with a forbidden voltage it is possible that some transistors that should have been off were on and conducting, which depending on the circuit design could have effectively resulted in an internal short circuit across the power supply leading to excess current flow through the effected transistors for a brief period before at least one of them was burn out. The second issue is that the Fire button inputs are pulled high by a 10K resistor, even if you use a low current LED (i.e. 2.8V @ 3mA typical) and it does actually conduct... a) You may have difficulty seeing that it is on at all as @ 10K the current through the LED will 500uA (0.5mA) b) Even if you lowered the resistor to provide the relevant current a 2.8V drop puts the input voltage at the input high threshold so you would never detect an input as the voltage does not go low enough. Personally I am at a loss as to what purpose the LED's serve beyond testing that the Joystick is working as you're not likely to be looking at them during game play and if testing is the only purpose then it is easier to just build a test circuit to plug the joystick into than to mod the Joystick itself. That said, if you do want to do it then it would be better to wire the LED's and their current limiting resistors in parallel with the existing input circuits (Between 5V and the joysticks switches) as per Danjovic' post. Design for the worst case scenario which is that a fault occurs and all 5 LED are on simultaneously, with a standard LED running at its typical 10mA current that will be a 50mA draw, if you are concerned that may be too high then use low current LED which should give a 15mA draw running at 3mA current each.
  11. With no disk you should be seeing the LASER head unit move towards the centre of the disk to read the TOC and the laser itself move up and down as it tries to focus no the non existing disks. If it is doing all that then as you say the issue may be with the laser itself. Did you try cleaning the lens in case some dirt is affecting it? If not you could try soapy water and then clean water to rinse (apply using cotton bud/q-tip), isopropanol or a camera/spectal lens cleaning solution. If you are certain the unit is producing LASER light which may be visible with a digital camera (always avoid looking straight at it the the naked eye ) there should be a plastic section roughly in the middle of the flex circuit where it changes direction by 90 degree from the head unit to go to the PCB, if memory serves there is a very small and fragile potentiometer there that can be used to adjust the LASER power. If trying that you will need a small screwdriver and an steady hand, it is not something I have tried so I am not certain which direction you will need to adjust it but I suggest marking it current position before you start and place other marks at 45 degree each side from there and if you can a mark midway between the initial position and the 45 degree (approx 22 degrees). Then first try both 22 degree positions and then if no joy try 45 degree positions as you do not want to turn the power up too much and cook the LASER diode.
  12. The CDM 9/44 is a typical CD unit from around the early to mid 1990's. We have an undergraduate lab at work which has Phillip CD players of that era with them in. They are very hard to come by these days, the last time I looked for one they were priced at around £120-£150, pretty ridiculous when you can but a cheap separates CD for about £40. About 15 years ago they were about £30 each. The CDM 9/44 is essentially a dumb unit, it just has the Red/Black power lead for the motor and the flex cable which powers the LASER unit, receives head position signals from and sends focus, tracking and data signals back to the main controller IC. CD transport mechanism units today should essentially be the same as they were then, it is just the physical appearance and mounting points on the motor drive/head unit that will change, so you may be able to use a different unit provided you can find a way of mounting it where it needs to go. You could try looking for other CDM9/ mechanisms, I am sure the numbers after the slash will mean there are some differences but they may be the closest in terms of size, shape and mounting points to the /44 to be usable. However, being the same vintage they may be just as rare and expensive. It is difficult to tell from that image so I may be wrong but to me it looks like the power switch has two mounting flanges (nearest to the viewer) and two pins for the actual switch contacts which would make it a single pole, single throw (SPST) latching , probably 3 or 4 amp. I presume the on/off plunger is centrally located between the mounting screw holes in which case if you cannot find the exact replacement just try and find one that physically fits inside the case with the same screw hole panel mounting points and solder wire between it and wherever it connected to on the main PCB (I am assuming there was a wire connection between that small switch PCB and the main PCB)
  13. Another Atari lives again. You did most of the work, with the information you provided, for me a missing clock or reset issue seemed the mostly likely explanation and thus the next things to check.
  14. If that is the case then the values make more sense with the exception that the voltages for pins 10, 11, 12 & 13 are those for the on state as so that at least in part explains why the Lynx is on. Possible causes are a fault with U6, a stuck On button , a problem with C38 or possibly a problem with Q7. First disconnect the button (narrower) flex circuit from its socket, if the Lynx still immediately powers on when the AC adaptor or batteries are inserted we can eliminate a stuck "On" button. If you have a small piece of (preferable solid) wire (i.e. a paper clip) use it to connect pin 7 of U6 to either Pin 11 of U6 or the bottom end of R70 (right of U6) for a couple of seconds, that should be enough to switch the Lynx off. If it does, does the Lynx remain off when the wire is removed or does it only remain off while the wire is in place? If the Lynx remains off with the wire removed does using the wire to link pin 14 of U6 to either Pin 11 of U6 or the bottom end of R70 turn it on again?
  15. If you perform a search of the internet or the 2600 forum you should be able to find a copy of the 2600 field service manual which may help you to diagnose the problem. Did you check for the clock on all the relevant pins, TIA pins 4, 11 & 26, 6507 pins 26 & 27 and pin39 of the RIOT? Also check that pin 32 of the TIA is taken to ground and that the reset pins of the 6507 and the RIOT (1 & 34 respectively) are pulled high to 5V.
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