Amiga FrameGrabber. Software version 3.8. Hardware revision 6. (C)1997 LJS. Check your hardware is up to date!!!!!! If you`ve already read this, read it again. There are changes! Fast Data Aquisition! I will not be held responsible for: Any damages or injury due to misuse or incorrect construction of this device. Any loss/corruption of data resulting in the use of this device. Incorrect information given in this archive. Use of this device/software is at the risk of the constructor/user. The software/hardware works and I have them here as proof !!! Shareware. This project and included software is shareware. Registration fee is 10 pounds sterling. This is a small price to pay considering the amount of work and research that has gone into producing this. What you will get. You will get any later versions of the software and details of any modifications/improvements to the hardware. You will also get any source code and other files produced during development of this project! That alone is a disk worth of junk ;-) Film etc. Remember you dont know who gets hold of your piccies if you release them. If you are capturing from films etc... 20th sweaty sox or whoever may take offence if you are using their stuff from films and using it to advertise breath mints or something. And then you get fined by the nuts for some junk you dont really care about. I have changed the example file for this exact reason!!!! Included files. You should find in this archive:- 3 IFF schematic files. This file! And the frame grab software. Some example piccies. Getpar (The faster transfer software) Getpar.readme Frame Grabber. I needed a device which would capture a single frame from a video signal. The frame grabber described here has only been tested with the British PAL system. Other PAL systems should work although I don't know about the NTSC system. The SECAM system may also work as this is quite similar to the PAL system. The only thing that would prevent the grabber to work on different systems is the polarity and periodic time of the horizontal and vertical sync. pulses. Also the bandwidth of the input signal to the grabber will affect the results. This project works on the PAL(I) standard. It will probably work on most other video standards. Here are the standards for other places if you dont know what you've got! PAL(I) Gibraltar, Hong Kong, Malvinas, Republic of Ireland, UK. PAL(B/G/H) (This should work) Afghanistan, Algeria, Australia, Bahrain, Bangladesh, Belgium, Bosnia Brunei, Central African Republic, Denmark, Equatorial Guinea, Ethiopia, Finland, Germany, Ghana, Greenland, Iceland, India, Indonesia, Jordan Kenya, Kuwait, Liberia, Luxembourg, Malaysia, Maldives, Malta, Mozambique, Netherlands, New Zealand, Nigeria, Norway, Oman, Pakistan Portugal, Qatar, Serbia, Seychelles, Sierra Leone, Singapore, Spain Sri Lanka, Sudan, Swaziland, Sweden, Switzerland, Tanzania, Thailand, Yemen Arab Republic, Turkey, United Arab Emirates, former Yugoslavian territories, Zambia. NTSC(M) (Dunno about this, probbably work though) Antigua and Barbuda, Bahamas, Barbados, Belize, Bermuda, Bolivia, Burma Canada, Chile, Colombia, Costa Rica, Cuba, Dominican Republic, Ecuador Guatemala, Haiti, Honduras, Jamaica, Japan, Kampuchea, Mexico, Micronesia, Nicaragua, Panama, Peru, Philippines, Puerto Rico, Saint Christopher and Nevis, Saint Lucia, Samoa, South Korea, Surinam Taiwan, Trinidad and Tobago, United States of America, Venezuela. SECAM (This is similar to PAL) France, People's republic of China, most African territories not already listed, most areas of the Commonwealth of Independant States and former Soviet satellite nations. Let me know if I have missed you out or misplaced you! Operation. The unit when built is simple to operate. A composite video signal is connected to the input of the grabber (get this from the back of your video recorder (Most have a video in/out and audio in/out connector)). Play the video tape you want to grab pictures off and when the picture you want comes up press a nice capture button on the front of the unit. The next video frame will be captured (this process happens very fast). After you have your image captured all you do then is transfer the data (128kbytes worth) into your Amiga. This is done through the parallel port. Then the image is decoded by the frame grab software into a normal IFF picture which you can edit (Print out and make posters for your propaganda, obey me or 'I'll be back' etc..) The parts. You shouldn't have much trouble in obtaining parts for the frame grab. Saying that I have heard that the 74123 is hard to source since it apparently isn't manufactured anymore but I am looking into this. *I have looked into this and removed the chip from the design *8-) Most parts are standard components (There aren't any weird martian components in it). The only two chips that may cause a problem (apart from handing your hard earned cash over for them) are the 128k memory chip and the Flash A/D converter (They aren't that obscure, most electronics places should have them (Maplins definite in UK)). All the other parts are widely available. Further stuff. I think I will be keeping this project up to date. Speeding things up and improving picture quality, bringing the construction costs down that sort of thing. So you know if you build this thing then you can be sure of further developments on it popping up allover the place. My approach. The grabber is pretty much straight forward. The video signal once inside the grabber is split up into three bits. The unchanged video signal goes directly to the A/D converter. From the video signal the horizontal (H.sync.) and vertical (V.sync.) sync. pulses are split out from the rest of the junk. The H.sync. pulses which occur at the beginning of each TV line are simply stored on bit 7 in the RAM and do nothing else in the circuit. The V.sync. pulse goes to an input of a AND gate. The push button (grab button) simply sets a Flip-Flop after being debounced by another Flip-Flop. When the output from the Grab button flip flop is high AND a V.sync pulse is detected yet another flip flop is set. This last flip flop enables an oscillator which runs at 6.5MHz (In theory a signal should be sampled at twice its maximum frequency so for a video signal the sampling frequency should be 11MHz but in practice you can get away with just over (6.5MHz). If you own a sound sampler you will know you can get acceptable results when you sample at some stupidly low frequency like 8kHz, in theory you should sample audio signals at twice the band width. The band width for audio is 20kHz (Hi-Fi) so you should sample at 40kHz but you don't need to in practice). Boy that was a long bracketed thing wasn't it? The oscillator clocks the A/D converter and a large binary counter (used to address the memory chip). Each sample is stored at a different address in memory. The grabber resets all the flip flops and stops the oscillator when the memory chip is full (It also resets the address counters). The oscillator is infact a free running oscillator, the output is just gated with an AND gate. The data held in the RAM is then ready to be transferred to the Amiga. All this thing is, is an electronic 'gear' it slows the video information down to a speed the computer can handle. If you had a computer which could access the parallel port at video speeds you wouldn't need this equipment. BUT your stuck with slow parallel ports so you have to build this *8-( Power supply. The power supply for the main board is 5 volts (surprise surprise). The project includes its own regulation circuit so you can stuff in any voltage between 8 and 35 volts (I think its 35V I cant be bothered searching through data sheets to find the correct value). Supplying the maximum would be stupid, the power regulator would get very hot and probably decide to output the full input voltage, blowing up all your expensive chips. A sensible voltage to stick into the regulator is 8 volts. Personally I wouldn't go for anything above 12 volts though. Saying all that I have designed the power supply bit with a 'crow bar' circuit stuck on its output. If the regulators output voltage should rise above about 5.6 volts it simply shorts out the output, instantly cutting power to the board and blows the safety fuse (good eh?). One of those adaptors you can get from Tandy or other places will do. If you have something like a games console you could throw away the console and use the power supply to power the grabber {8-). An old Spectrum supply or even a Commodore 64 supply would work fine (I didn't like the C64 I had a nice Commodore Plus 4. I also had a plethora of ZX Spectrum's but alas they are all a bit strange now (2 half work in a strange 16k mode!)) Yikes I've only been typing half an hour and look at all the junk I have churned out! Oscillator. The oscillator is a crystal controlled one. Comprising of 3 inverters, 2 resistors, 1 capacitor and the crystal. If you want you could replace the oscillator with a ready built clock module operating at the same frequency as the crystal. This has no benefit only it makes the construction very slightly easier (Saves you soldering 4 components woopee). I haven't tried the module thing so don't blame me if you decide to be lazy and stick one in and it doesn't work. (Anyway what's wrong with my circuit?) Decoupling. The circuit should be well decoupled with capacitors. The capacitors of about 100nF should be soldered directly across the supply pins of the chips. This could be done on the solder side of the board. This simply removes any electrical noise on the supply. When I was building this I went over the top a little with the decoupling but this has no side effects. Construction techniques. There is no PCB yet (and is unlikely to ever be one). It could be built on strip board. Mine is built on general purpose printed circuit board. Thousands of holes with copper pads for each hole on the other side. All the connections are made with solid wire. Telephone extension wire has a rubbish plastic insulator which shrinks like mad when heated! Computer communications cable seems to work best. LAN cable is widely available and comes with quite a few conductors, A meter of this cable should see you through this project with ease. Anyway its up to you to construct in the way you are most comfortable. Box. If a metal box is available use it. I used a box from a bit of old British Telecom equipment I bought from an electronics sale. Although shielding would be recommended I don't know if it has much effect in this project. All I did was back a sheet of aluminium foil in sticky back plastic on both sides and hot glued this to the inside of my plastic box! If you don't want to fork out for a metal box a biscuit tin would work. It may look a bit crudd when you have finished but screening is excellent. If it works for a pirate radio transmitter this project will be no problem! Parts list. Wot u need. IC's 1..74HC04 (OR LS but HC is better ;-) 2..74LS74 1..74LS08 (RECOMMEND 74HC08 SEE TEXT) 1..74HC4040 1..74HC4024 1..CA3306 FLASH A/D 1..431000 (85ns CMOS STATIC RAM 128Kbytes or 1Mbit) 1..7805 1..CF106D (THYRISTOR (SCR) SEE TEXT) Discrete components. 6..BC547 2..BC557 2..LED'S 1...75R 14..1K 5...2K2 1...10K 2...470R 4...47K 2...18K 4...4K7 1...33K 1...5K MULTI TURN PRESET 1...10nF 1...68pF 1...560pF 5...100nF 2...1nF 1...15nF 3...220nF 2...10uF 1...22uF 1...1000uF 4...1N4148 (OR 1N914) 1...5V6 500mW ZENER (SEE TEXT) 1...1A FUSE (AND HOLDER) About 10, 100nF caps. for decoupling. 25 pin male D connector. Board, Box, Phono plugs(Video input) , SPDT pushbutton See text stuff: The SCR, Zener, and associated components (shown in dotted box in PSU schematic) can be omitted if you want. These are included to provide a 'crowbar'. Should the 7805 fail due to some weird space ray or something the SCR will switch on, shorting out the supply and blowing the 1A safety fuse. This stops any of your chips being fried (with a nice piece of cod and a tub of peas please!) Dont use a 74LS08 in place of a 74HC08. Some LS's may work but its a bit dodgy. Because I have used two diodes instead of an OR gate the level at the other side of the diodes may not be sufficient enough for the counters to see it a a valid logic level. So use HC. ***************This bit has changed**************************************** Setting up. After building there is only one piece of setting up to do really. With a volt meter set the voltage at pin 9 of the ADC (CA3306) with the aid of the multi turn pot. to * 1.25 volts. * <<<<