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YannAros

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About YannAros

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  1. Hi @the_crayon_king Some thoughts about your 240p concern. I do not think this can be a problem, the timings must be NTSC or PAL compliant, so there must be the right number of line! For PAL, VSYNC happens every 20ms (50 frame per second), HSYNC happens every 64µs (~15kHz), that make 20ms / 64µs : 312.5 lines per fram that is according to spec for a non interlaced PAL signal I imaginet timings for NTSC are 16.6ms per frame with same 64µs per line, and therefore around 260 lines / frame. From this lines the intellivision is only able to draw 192, some are blank at the beginning and at the end. These timings must be respected otherwise no CRT would be able to display anything. Otherwise your investigation is very interesting and you latest plots show that you should be able to get something soon. I'd use V3 as a base for HSYNC, then recreate a pure VSYNC from maybe V1 and V4. Once this is available CSYNC can be created by merging H and V SYNC using one of the conventional methods. I need to free up some time on my side to investigate on this.
  2. @Icelvlan Unfortunatelly this will not help as composite and LUMA signal (if it exist as is) do not have these sync pulses either. From start Intellivisions do not have a proper CSYNC signal, this wasn't an issue with older TV sets, it became with more modern flat screens. Today we are faced with 2 issues: - Modern TV do not have anymore analog demodulators, and when they have one it is not a good one - SYNC signal is not "good" enough for some TV and other devices (OSSC) even when adding an RGB mod @the_crayon_king is working on adding sync pulses in the signal that the STIC is generating in order to overcome the "design flow" of the original chip. There is another way that many of us are using today, it is to find a TV or device that copes with Intellivision sync signal. May be OSSC should be updated instead, it might help not only for Intellivisions but also for other retro devices.
  3. @the_crayon_king, it looks like the way to go but as you say it is quite complex and might even not work, nobody nows exactly if the missing pulses are the reason why OSSC is not syncing on any known RGB mod for the Intellivision. My obervations with simple RGB input from modern TV is telling me that there is also a timing problem : why does it work by simply adding a capacitor between sync and GND?
  4. Hi, My mod has not yet been tested on NTSC models, theoreticaly it works but before going further I'm waiting test results from @-^CrossBow^- It's however proven as working on SECAM (modified PAL) models and has the signals are taken before the SECAM modification it works for sure on PAL models. I do not have all those models and can't guide on how to install the mod in all variants.
  5. Let me try to explain the situation in France. France is using SECAM modulation for the RF signal. Initial Intellivisions where PAL models modified with a daughter board connecting in place of the LM1886n found on the PAL boards. For these boards you can use a simple 3 bit DAC per color as the conversion from Vx signals to digital RGB is already done. I believe that for cost reduction a new PCB was created where the Vx signals are transformed to SECAM modulated signal without going through RGB signals. These boards also include the power supply, output of the transformer is going directly to the motherboard and redressing and regulation in done there. It is for these boards mainly having a serial number starting with RH that I’ve created this mod. The form factor is just a very good fit for those. A new layout with a new for factor can of course be done if there is enough interest.
  6. Hi, I've studied a bit the CSYNC stuff, and ended doing 1XXX1 (V5 to V1) that seemed to work with my LCD TVs, then I've found another TV that wasn't syncing good horizontaly. Feedling around I could obtain a stable image by "delaying" the sync signal adding a 47nF cap between sync and GND, however as you delay the sync signal the image gets shifted towards the left. Playing further I've found that using 1XXXX is working on this LCD TV, but not on my other ones working with 1XXX1. Later on I've found another LCD TV that had the same behaviour requiring 1XXXX and some other users of the kit had to do the same. So my PCB comes with a jumper allowing to select either one of these methods. I'm also using V5 as OE input for blanking as you suggest. I took a look at your schematic, that from a high level should work, I didn't look into the details. Mine is using separate resistors for each RGB of each colour, allowing more control over the end result. One thing also regarding component selection, I've done it so that I can get the full PCB assembled and SMD component mounted by JLCPCB, this way, even if the component is a bit more expensive, I have no complex soldering to do. At the end we are not talking about huge costs (assembled PCB for a batch of 30 should be around 4$ without shipment cost and custom fees), I'm adding connectors for convenience but you can solder wires directly on PCB to. This is what it is ooking like in the French Intellivision model that has embedded power supply, I designed it so that it can be mounted where the power supply PCB usually sits:
  7. Hi, I'm the "creator" of this other solution. You can see the schematic and even downlod files from here : https://easyeda.com/yannick.erb/Intellivision-Secam-RH-RGB-Mod_copy The inputs are taken from the STIC directly (V1 to V5) other inputs are Audio, GND and power, so nothing PAL specifc. The aim was to create a very simple kit, not necessitating any specifc tools to build it. The palette is however not easily changed, you need to modify resistances values and there is no fancy functionality on it. The only specificity is that the sync signal can be either NOT(V5 AND V1) or NOT(V5), the second solution proved to be working with many modern screens where the usual solution was not working leading to loss of horizontal sync. I have never tested (and I don't know of anyone else) with OSSC. Best regards, YannAros
  8. Hi @decle, Is there any more information available regarding the firmware to mimic the cartridge on a TeenSy 3.2? A simple "diy" cartridge emulator would be a welwome low cost alternative to LTO Flash.
  9. I’m not going all the way to hdmi but rgb to hdmi devices are available from many places and might do the trick
  10. Did anyone investigate lmh1980 or lmh1981 IC to extract and reconstruct sync signals on an Intellivision?
  11. The funky non-compliant sync signal problem isn't solved, but what I've found out is that if I use "V5" inverted as a sync signal I have a nice stable picture on my 2 monitors that didn't work cleanly with the standard sync signal. I've put the possibility to switch between these 2 solutions on the PCB. My investigations tend to tell me that the issue is not the missing HSYNC pulses during/around VSYNC but the length/position of the HSYNC pulses. I do not have an OSSC, but 2 monitors that didn't sync correctly, for both of them, I was able to display an image by filtering CSYNC with a simple capacitor to GND or by using inverted "V5" as CSYNC. The sync is buffered enough by the 74HCT00 that can provide up to 25mA. Only 10mA is drawn from it's output (470 + 75 Ohms load).
  12. HDMI capable is a tad bit more complex. Best solution is to squeeze in the console a rgb mod like mine and a rgb to hdmi converter from Chinese vendor. I haven’t one myself so I can not test and point you to one that would be working. What is almost certain is that all of this will fit inside the Intellivision.
  13. A short youtube video to show the result :
  14. Dear All, Going further with these mods, it looks to me that the "Secam P2" mod should wortk on any PAL Intellivisions and that the "Secam RH" mod should work on NTSC Intellivisions. The projects are Public Domain: Version P2 : https://easyeda.com/yannick.erb/Intellivision-Secam-to-RGB_copy Version RH : https://easyeda.com/yannick.erb/Intellivision-Secam-RH-RGB-Mod_copy The only thing I ask for is not to resell them for more than 20€ for the P2 and 30€ for the RH. And if anyone make a batch of RH version to send me one exemplar as I have not enough pre-orders at the moment and will therefore not launch a build. If you'd like to pre-order one or the other of these versions just post here or PM me.
  15. Hi, If you're still interested in the subject for french/SECAM Intellivision RGB mod, I've worked on it and found several things: 1. There are at least 2 totally different motherboards with SECAM RF output First one, referenced mainly as 5156 / P2, has an additional mezzanine board developped by CGV (a french company) to adapt it for SECAM, it also has a specific "CGV" sticker on its back Second one, referenced as 5156 / RH, has a single PCB (even power supply is integrated) and is natively supporting SECAM, no modification is visible 2. I've created an RGB mod for the first version ("P2") that is tested and is working, it is close to the ZOE for PAL version. Some kits can be pre-ordered (I'm still waiting for some parts before I can send them out) 3. For the "RH" version, the mod is on-going, it is closer to what is needed for the NTSC version of the intellivision. First tests are showing that it shoudl work, but I couldn't finalise the mod yet due to missing components. As soon as I will have received my latests order I will confirm/infirm that it is working. You can find more details here (in french) : https://www.gamopat-forum.com/t109948-precommande-module-rgb-pour-intellivision-secam The schematics and gerber files will be published and open sourced as soon as I have confirmed everything is working.
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