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the_crayon_king

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About the_crayon_king

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  1. I originally wrote this on the inputs of the 74145 not the outputs of the 9322 thus the confusion. I confused myself looking back at it, so it prompted a rewrite. As mentioned previously if you are attempting the analog version of this then you get much less color accuracy. The expected colors for analog are posted above. Sync should also be buffered along with all the other bits. The sync thing shouldn't be an issue in testing, at worst it should just shift the video over slightly. I just need to correct the schematic/PCB. Sync shouldn't be inverted but if it is that would add an inverter to the BOM. I wrote the code to do this in VHDL for a CPLD; I may be able to convert it to whatever you have on hand. In the code I just wrote white as the "else" since I have all the other color bit values anything else should be white. I would almost expect that on no signal (besides sync) the Fairchild would default to outputting a white screen. Since all of the color bits I defined afaik make the voltage lower. To clarify by analog I mean a non CPLD/FPGA solution. I do not know the proper term for such things. As long as you have a oscilloscope testing for the colors should be as easy as putting a solid color screen up and testing the 9322 pins outlined. You will see up and downs for active pins but the 0's should be steady.
  2. You need to constantly be cleaning that freaking thing. Nozzle size is a big factor in clogging, another is filter replacement. One key thing is to hold the trigger for a few seconds after sucking a few blobs (that sounds weird) I usually tilted it backwards to hopefully get gravity to somewhat assist. If you need another sucker use this. <<this is not like the basic mechanical de-soldering pumps. It's malleable tip allows much better suction. Actually, that tool IMO is much better than the FR-300 (I dunno about the 301). Really, I am convinced they made the FR-300 crappy just to sell more of their 20$ tips. Typically I would use the FR for huge blobs and something else for smaller pins (like PDIP40).
  3. I very confusedly wrote the above truth table; I think I was switching the bits to match their significance. I have fixed this to be written against the outputs of the 9322 Since nothing else matters. I had to basically reverse the 74145 outputs all the way back to the 9322 thus all the confusion. THIS should be how to write it. 9322>74145 (what it will see) > what color the schematic says 0000>1000 8 > black 0001>1010 9 > grey 0010>1001 > 0011>1011 > 0100>1100 > 0101>1110 > 0110>1101 > 0111>1111 > 1000>0000 0 NC > 1001>0010 1 NC > 1010>0001 2 > bg blue; boost a sel 1011>0011 3 > bg green; boost a&b sel 1100>0100 4 NC > 1101>0110 5 > fg red; b sel 1110>0101 6 > fg blue; a sel 1111>0111 7 > fg green; a&b sel when looking from 9322 out ***1 b sel higher voltage than a sel **1* a sel lower voltage than b sel **11 a+b sel highest voltage *0** space boost on (adds small amount of voltage) *1** space boost off For the transition from 9322 to the 74145 last two bits get swapped and 1st bit is inverted. This is only helpful if you are trying to reverse engineer what they were doing. Any unspecified thing could be the value for white. I would suspect that would use a NC (not connected) pin so 1000, 1001, or 1100. Those are the most likely, but the only was besides guessing would be to put up a white screen and measure the output pins of the 9322 to see what pins are actually on. 1000 actually makes the most sense since it does not have any chroma/burst XX01, XX10, XX11 would all be some sort of chroma or burst. Then it has X0XX inside of it which is an increased voltage from space boost. White should be the max voltage with no chroma so that is my logic there. Any of the pins from the 74145 being active (off) will only lower the voltage so that is why I think it would have to be a NC pin. Ill have to fix the schematic for the PCB that is on easyeda to match this updated information. As it were you would only have to swap A and B around from how I had it so that it reads DCBA. I should deff validate what I have before anyone attempts to use that. The parts would all remain the same it is only the wiring that would differ; it would be best to breadboard this first and use a color test screen to validate.
  4. You mean the baby PAC man thing correct ? If you have an old CRT and wanted only YPbPr then most likely you do not need to convert to RGB. Converting from wonky YPbPr to RGB then back to a corrected YPbPr seems like overkill if you just wanted YPbPr. Just divide the inputs to acceptable levels 0.7v p-p or 1v p-p if sync is present then 6db amp and use. My crappy o-scope actually died so I haven't been able to actually test this stuff. There is alot of variance in the data sheet so the only way I see to do it with minimum parts is with potentiometers and measuring the outputs with a scope per console. as a note I am out of practice with this stuff; further note this should only be used with an old CRT TV or possibly a scaler. It is wildly unlikely it would work with a newer TV. just replace r1,r2,and r3 with pots and adjust . If the voltages are the same across many systems (which I doubt) then the pots could be substituted for resistors. To be clear for Y you need 0.7v p-p difference on Y from BLACK to WHITE (ignore sync) as in 0 0 0 to 255 255 255 for R-Y you need a 0.7v p-p difference from RED to CYAN as in 255 0 0 to 0 255 255 for B-Y you need a 0.7v p-p difference from Blue to YELLOW as in 0 0 255 to 255 255 0 If looking at a black and white screen and viewing Y you should see three distinct voltages the lowest one is sync. I have heard that R-Y and B-Y may or may not have sync (not sure) but the same would be true for them if sync is present otherwise: when looking at a red and cyan screen and viewing R-Y you should see two distinct voltages when looking at a blue and yellow screen and viewing B-Y you should see two distinct voltages if there were a third lower voltage it would be the aforementioned sync. These elements are what I am referring to when I say to adjust to 0.7v p-p and ignore sync. The best way to do this would be with a color test screen or something, a scope, and the rough schematic shown below with the substitution of R1, R2, and R3 I may be wrong on all that do your own due diligence. https://imgur.com/a/0kybwmf
  5. My o-scope is iffy. I got component to work with just sending the outputs of the TMS9928A through a 75 ohm resistor and 220uf capacitor. That kinda stuff will only work on a old school CRT and is not at all correct. another way to write this would be to look at the range 0.9v black to white min; 0.7v black to white nominal; 1.1v black to white max. 0.4v black to sync min; 0.5 black to sync nominal; 0.5 black to sync max. 1.3 white to sync min; 1.2 white to sync nominal; 1.6 white to sync max I do not think the input can be divided before going into the amp (I did not consider this earlier)., instead block the DC with 0.1uf capacitors if sync is present on R-Y and B-Y then you probably don't need pull up resistors. I will draw up what I am talking about later I have to backtrack a bit because I wasn't thinking about the offset.
  6. I can't get this to work on a modern TV without going through a scaler. Even if you could get straight component to work on a newer LCD TV it would look bad because the TV can't scale cleanly. I did get composite to work on a new TV but it looks terrible (poor scaling). The issue I was seeing is pixels tearing left or right from where they are supposed to be., but only on specific colors. There is also a sawtooth type pattern that was reduced by replacing either C49 or C28. I am not sure which did it. However I still see the remnants of that pattern on my no name video scaler VS my XRGB looks fine besides that tearing. I tried a mixture of my mod and the G7200 mod. I tried different setups for the THS7374. I tried adjusting the clock of the console. All methods seemed to be the same on my TV. (It's important to note I also have a different console and it had the same issues.) It's some sort of delay or timing issue. Also its interesting that the tearing and sawtooth pattern do not show up on my CRT even right next to the screen. Some improvement may be had with using a different method to sum the colors. The way I am doing is just cheap and easy but by no means perfect. I am curious if using a D-type flip flop with the NSTC clock would repair any of these issues. The other idea would be using an normal op amp instead of the THS7374. I am open to ideas. What I have laid out is basically a 'passable' way to get video out to a CRT in one form or another. I can button this up inside my console and live with it as is for my uses. I have written the code to do this same kind of mod but through a FPGA the problem there is I need a few things I don't currently have on hand. I will continue to tweak what I have but the end goal is a FPGA based mod which in alot of ways is easier. With a FPGA I could scale or re time the signals easily. Also it could be sent through HDMI. I also did some other things to get a nes controller and atari controllers to work on this console. You have to mod the nes controller but the atari can be used as is.
  7. I made a video but showing three video outputs. My setup is a pain to use so don't hate. Also I SUCK at this game. There are vertical jaggies on the video that I can't see with my eyes when playing on the TV but show up in the recording. There is also some haloing with blues: Installed: https://i.imgur.com/2BO0juK.jpg Low Saturation Medium Saturation Full Saturation RANDOM NOTES: The video is currently over saturated which is what these scope readings are showing. The ratio between low sat and medium sat is what matters most. The sum can be easily adjusted with the pulldown being higher/lower. It may be best to tie a pot between the pulldowns and ground so saturation can be adjusted manually. The ratio I am using is supposed to be 2.5. That is LS*2.5=MS., and MS/2.5=LS. MS+LS=FS LS should be around 408 MS should be around 1.020 FS should be 1.428 The reason I don't have closer numbers is because I do not actually have the specific resistors I need and had to daisy chain 5% tolerance ones. I need to change the capacitors and voltage regulator so some video aberrations could be from that. I played this on my CRT through composite and S-Video and it looks a 100 times better than through my scaler (XRGB). I will try component later but I would guess it will only give a slight improvement over S-Video. Here is showing my CRT:
  8. So RGB should be able to be taken from the 9322 (C2) For my uses I am calling pin 12 = Di pin 9 = C pin 7 = A pin 4 = B D is inverted from how you would see it at the 74145 thus the "i" ------------------------------ truth table DCBA 1000 = 0 NC > 1010 = 1 NC > 1001 = 2 > blue light 1011 = 3 > green light 1100 = 4 NC > White ? 1110 = 5 > red bright 1101 = 6 > blue bright 1111 = 7 > green bright 0000 = 8 > black 0010 = 9 > grey ------------------------------------ I could explain my logic but basically white is either 1000 or 1100. I did a first pass at trying to make a schematic for this: https://easyeda.com/hotdog6394/fairchild-chan-f-rgb TBH doing this with a FPGA would be far simpler. However, where is the fun in that ? Issues I am having is finding a pallet with decimal rgb values. I set 255 (714mv), 191 (534.8mv) and 0 (0). I only want to bother to set combinations of 3 specific values., so if someone has better values to shoot for let me know. This is the colors with what I have (randomly) chosen so far: [note this is not on the console (yet) just a color representation of what should be possible with the above circuit]
  9. I am pretty sure the change you have is from a lower value resistance on your pullups. I literally had the scope connected while I shorted 5V to the output through 10k so I don't think I made any errors. Damaging some easily replaceable ICs is one thing but if the 2637 goes out its game over. I had the pullup active for an hour or so I am not sure when the issue happened since I wasn't testing that part at the time. I only had the pullup on one line and that is the one that burnt up so yea Id rather keep the OEM circuit untouched and I cant see a way to do it without a op amp > buffer > op amp. I did manage to get SD video out through an expansion circuit so CV, S-Video, and Component is easily made with an additional board. That thing was held together on hope and nothing else so I couldn't test much further. I will have a prototype design ready to print tomorrow evening I am confident it will work.
  10. I am not too concerned with the measurements downstream they are not where I will be tapping. Just looking and they look gross. I took measurements with pullups but no change I can only assume there is already a pullup applied with 1V. That is the only reason I can figure for no change with a 10k on 5V. Since I added pullups and then one of my lines of the LS burnt up I can only assume the two are related. I try to concentrate on the best ways to do things without changing the existing circuitry. So the best way I can figure is : amp with 12db gain on outputs of 2637> into logic buffer with OE tied to blanking> into resistor/divider to THS7374. I am certain this combination will work I just don't have the parts around to test. If inversion is still an issue the buffer would just be a buffer inverter. It is interesting that the other truth table was inverted from mine exactly. Looking at the signal itself it doesn't appear to be inverted. Usually an inverted signal would be constant high with a few lows to indicate whatever. And from what I have seen that is the opposite. I just have my one test build of having inverted colors to go off of. Since inverters/buffers are pin compatible its not an issue and I will begin an actual PCB design soon.
  11. That pin doesn't have any voltage on it that I can tell. If it did have voltage I assume it would invert. From booting the console and starting the game I didn't see it trigger at all. 2637 output > https://i.imgur.com/BWsmV5d.jpg 74LS86N output > https://i.imgur.com/F25h9K3.jpg 4069 inverter second output > https://i.imgur.com/lKvinuC.jpg 2622 sync output > https://i.imgur.com/ZO1l16d.jpg You can see the signal from beginning to end; more or less. It's not inverted. So I'd assume that the output of my buffer would match. Look how degraded the signal gets at the inverter. The first inversion is just as bad so I didn't take any photos. Sync is not ideal either. Now lets see what happens when I add a pullup or short the 74LS86N to 40 line to 5V With pin 40 NC https://i.imgur.com/g7MICzq.jpg RED pin 40 NC https://i.imgur.com/kLYJbXs.jpg RED pin 40 connected https://i.imgur.com/4rgKI5x.jpg So pin 40 seems to invert the signal when floating somehow even though the other XOR is grounded ? More importantly with a 10k pullup I noticed absolutely no change in the signal at any point.
  12. Disabling the RF was the first thing I ever did so I have never paid it any mind. I tried with and without caps. Any impedance issues would have to be on the input of the amp anyway. Also tried with the LPF off and on. I think the possible inversion has to do with the weird way they are using the 2637 and 74LS86N. Normally for open drain you would have two states ground and a high impedance state. Right ? I think its meant to be used as 0 is 1V and 1 is float; but I think they are using it in the opposite manner somehow. Really I have no idea Im just going to use an inverter instead of a buffer and see what happens.
  13. Id be using the 3.58 ish mhz clock. I want to see if clocking will remove some aberrations I have in video. See those white lines on the robot ? Ill be doing both clocked and unclocked. I also need a clock for video encoding the lower formats y/c, cv, ypbpr. So the clock will more or less be input someplace either way. I had this working with pull ups and it inverted the colors. Else I can't imagine what I could have done incorrectly enough to reach black being white and white being black. I tore it apart since its a mess anyway and also my 74LS86N blue line stopped working. So I can't even do this with just an op amp anymore. I have a kit for the O2 that I have to pick up then populate that will work for this. If the colors are still inverted with that Ill use an inverter instead of a buffer. I will retest after getting all the parts I need. I would recommend any DIYers to just try an op amp THS7316 or THS7374 with resistors (on the spots shown above keep in mind you have to drop the voltage alot) It's cheap and dirty but gave me this:
  14. Ok well this screen shot is from Mobile Suit Gundam take note of the issues. Namely rounding of pixels here is a close up of some mountains or something: Any ideas ? Im going to replace all the capacitors I guess idk.
  15. I have jumped L4 and L5. Note that video out from the 74LS86N had warped lines. These other points seem to be better. Which are right after the 4069. Which is convenient since its also next to the outputs for the composite mod and sound. I also measured outputs of the 2637 and got around 1v p-p as well. Output from the 74LS86N was around 3.3V. Sync output was also around 3.3V. I didn't write down the exact values. Now I have to set everything back up and measure from the 4069 output I did test and get video however, The CV mod was done following a guide by GameTechUS > https://www.youtube.com/watch?v=TAuMRMaBM-o This should be a good kick off point for anyone wanting to do a simple RGB mod. Specific circuit to come soon.
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