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jamma again |
Xavier - Mar 14, 2002 |
ExCyber | Mar 14, 2002 | |||
I'm not sure that this will work for interlaced, but it's probably at least worth a look: http://www.keohi.com/keohihdtv/usefulinfo/vga_cabl... |
Xavier | Mar 14, 2002 | |||
hmm computer to hdtv close but no cigar thanks for tring though |
ExCyber | Mar 15, 2002 | |||
It at least confirms my suspicion that RGB -> YUV/YIQ can be handled by some op amps plus a bit of logic to inject sync. I haven't really analyzed the circuit, but there's a couple issues that need to be looked at if you'd want to apply it: 1) Ensure that the sync generation works for an interlaced signal. 2) Ensure that the reference levels are correct (I don't think this is critical but the picture would suffer without it) Anyway, this is the closest thing I've found so far... what I'd really need now is a circuit to convert from YIQ/YUV to Y/C (S-Video), because I don't really understand quadrature modulation... |
Xavier | Mar 18, 2002 | |||
ok I went out and got an old 9 pin sony rgb monitor for $30 at a used computer store hopefully this'll work , I also went to local arcade parts/sales store and got a used up 2 player 14 button controll panel for $25 . Now its got 3 switches on it . I know you put the proper ones on the NO part of the switch which part do you put the ground to ?(nc) Which ground of the jamma harness do you use for the ground ?(last 4) I bought a jamma harness with all the wires already on it , to some parts of the power supply there are 4 cables going to it , that should work the same though right ? because in all the diagrams they had one without wires and soldered the two pins together then soldered those two wires together . Also on my pc power supply I noiced on one of the main ones I get most of my power from that there are two ground instead off feeding all the ground to one like everybody else did I split them up between the 2 . But Ill probably have to take some off once you tell me which ones to use if I had to guess id say the last 2 to the last 4 depending on how many controllers you had |
IceDigger | Mar 18, 2002 | |||||||
it doesn't matter which pin of the button is hooked up to GND, and it doesn't matter which GND you use (as long as it's not video or audio GND).
you can use one of the GND lines alone, that'll suffice. just make sure you solder the top and bottom pins for each power line together, i.e. the first 2x2 for GND, the next 2x2 for 5V, etc. also, you usually don't need to connect the last 4 GND pins, since 99% of the boards link the first 4 and last 4 anyways. |
Xavier | Mar 19, 2002 | |||
ok I plugged it in and turned it on Got power Got sweet sound Got no picture its all scrambled Im using a 9-pin adapter sony multiscan using the specs from cps-2 build a jamma now it says ground to 1&2 unfort. the cable that came attached to my harness only has a few metal wires coming from it maybe if I cut of the head of the connector and splice all 3 of these cables together thatll work better . Im also off to see If i can find these specs of apple rgb monitors to jamma I fond before , maybe its an apple monitor . Its called a Sony Trinitron Multiscan HG Super Fine Pitch . Its calls the input in the back RGB INPUT and has three colrs red green and blue on the front , thats why I got it . It was manufactured in 1990 . Im off also to see if I find any info on it on the net , let me know if you can think of anything . Thanks |
Xavier | Mar 19, 2002 | |||
Sony CPD-1304 Specifications Looks like this mointor wont work Bastards hope they give me an exchange or a different monitor . Screen Attributes 14" Trinitron 13.0 viewable image .25 mm dot pitch Input Signal Video Signal : Analog H Frequency : 28-50 Khz V Frequency : 50-87 Hz Sync Signal : Composite, Green Video Bandwidth 50 Mhz Input Connector DB-9 to HD-15 Maximum Resolution Maximum : Up to 1024x768 Macintosh : 832x624, 75 Hz Flicker free : Power Use Power Supply : 100 watts Consumption : Compatibility Mac Adapter : Mac PnP; Mac Sync PC Adapter : User Controls Analog controls BR, CT, VE, VS, HZ, HS Plug and Play Dimensions and Weight Height : 13.7 Width : 13.9 Depth : 16.2 Weight : 28.6 Regulatory Compliance EMS EMI : Safety : X-Ray : Radiation : Power Saving |
IceDigger | Mar 19, 2002 | |||
eh, yeah, that won't work.. that's a VGA monitor. go for an amiga monitor, such as the 1084 series, or an atari 1435. |
Xavier | Mar 19, 2002 | |||
ok i got the ad724 chip and ad725 chip in the mail today , (we were dicussing in an earlier thread )hopefully I can get one of these to work if you go to there main websight theyll overnight you a sample of these chips for free .(please dont ask them for this if you dont have a purpose for it or even know what it is) Im sure this costs them about $20+ Anyways if anyone can help me decipher the schematics quicker id appreciate it . I think I have them figured out except 1 hows many amps can this chip handle ?( because i see itll take +5 volts will I need to attach another fuse if II power from my pc power supply ) 2. There arnt any other extenal parts I need are there ? 3. do you think these will synch low enough ? heres the links . http://www.analog.com/productSelection/pdf/2302_0.... http://www.analog.com/productSelection/pdf/AD724_b.pdf |
ExCyber | Mar 20, 2002 | |||
1 hows many amps can this chip handle Depends on what you're talking about. The appropriate values should be in the "absolute maximum ratings" section of the datasheet. There arnt any other extenal parts I need are there Yes, there are. Most importantly, you need a clock source. IIRC, the AD72X series will take either 4x or 1x the frequency needed and can be connected directly to a crystal, but I'd need to check. You'll probably also need various bits to condition/terminate the signals, but nothing heavy AFAIK (unlike some encoders that require a delay line and other stuff). 3. do you think these will synch low enough Yes. They're designed for NTSC/PAL, so there should be no problem with sync rates on standard res games. Meidum-res and High-res games are another story (though I think a standard VGA monitor will handle high-res). |
mal | Mar 20, 2002 | |||
The Data Sheet for the AD725 has an example circuit, but it refers to displaying VGA on a TV rather than RGB. I'm sure it could be adapted for RGB easily enough. Presently I'm considering cannibalising a defunct Saturn for the Sony CXA1645M on the main board. |
Xavier | Mar 20, 2002 | |||
>>>Depends on what you're talking about. The >>>appropriate values should be in the "absolute >>>maximum ratings" section of the datasheet. I didnt see it there thats why I asked |
ExCyber | Mar 20, 2002 | |||
You're right; apparently this isn't something they evaluate. However, I doubt it's much of a problem unless you directly connect the outputs to ground, and maybe not even then (seems to me they would want to design it to be tolerant of a short in the TV or cable). |
Xavier | Mar 20, 2002 | |||
ok well Ive got video I went out and bought this monitor for $35 : Magnavox CM1352 Specifications Screen Attributes 14" 13 viewable image .42 mm dot pitch Input Signal Video Signal : Digital H Frequency : 15.7 Khz V Frequency : 47-62 Hz Sync Signal : Separate Video Bandwidth Mhz Input Connector 9 pin Maximum Resolution Maximum : 640x200 Macintosh : Flicker free : Power Use Power Supply : Consumption : Compatibility Mac Adapter : None PC Adapter : User Controls Analog controls Plug and Play Dimensions and Weight Height : 15.5 Width : 14.5 Depth : 15.4 Weight : Regulatory Compliance EMS EMI : Safety : X-Ray : Radiation : Power Saving I used the specs floating around on the net for rgb 9 pin , cept it didnt work So I took off the cync and put ground on pin 7 alone and that worked wonders !!!!!!!!!! Now I gotta hook up my controll panel |
ExCyber | Mar 20, 2002 | ||||
I wonder what possessed them to spec it at 200 lines... you might want to check and make sure that the top/bottom aren't getting cut off (standard res games are 224 lines if I'm not mistaken), but I suspect that this spec is just wrong. |
Xavier | Mar 20, 2002 | |||
http://www.ionpool.net/arcade/tech/monitor...nch.pdf loist of other monitors i think would work |