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Member Since 13 Jan 2015
OFFLINE Last Active Today, 3:30 AM

#4244205 Whole bunch of 4:3 LCD SVGA monitors

Posted by emerson on Sun Mar 24, 2019 2:24 PM

I would be interested in a 15khz monitor regardless of its size.

#4239263 Intellivision II video problem

Posted by emerson on Sat Mar 16, 2019 12:21 PM

My first guess would be bad a graphic RAM chip. What model intellivision is this?

#4232481 Intellivision ntsc rgb mod design help

Posted by emerson on Tue Mar 5, 2019 7:45 AM

I recently acquired an Intellivision 2 to test the mod... and unfortunately it doesn't quite fit. The video connector is off center by ~1.5mm. Just enough for the video cable not to fit. This affects only the mini DIN pcbs since the dsub 15 pcb will require case tooling anyway. Also, the solder pad for the video pin does not line up correctly. A jumper wire or bent resistor lead will be required for this first run of boards. This means I'll have to design separate pcbs for the Intellivison 2.


On the plus side, I have created replacement parts lists for:

- mains power cord connector for 2609

- electrolytic cap kits for both 2609 and 5872

- ribbon cable for 2609 power board

- reset button for 2609

- reset/fast switch mod for 5872

- pin header for 5872 power board

- power cable barrel connector for 5872


I have also designed breakout boards for the COLOR and SOUND chips so no more bending leads and soldering directly to chips!


Lines up well on the 2609...



but not on the 5872.



Lines up well on the 2609...



but not on the 5872.


#4225465 Intellivision ntsc rgb mod design help

Posted by emerson on Fri Feb 22, 2019 8:50 PM

I did some more testing with the cheap hdmi video scaler and had good results. I tested an Emerson LD190EM1 lcd tv and a Sony Wega KDF-55E2000 rear projection tv and the picture looked great on both. No haziness between the letters at all. Removing the series capacitors on the rgb wires of my scart cable had little effect on the picture so I left them in. Unfortunately the pictures I took don't capture the quality. The lcd that gave the bad results was an LG 19LH20-UA.


Emerson LD190EM1



Emerson LD190EM1



Sony Wega KDF-55E2000



Sony Wega KDF-55E2000


#4225301 Intellivision ntsc rgb mod design help

Posted by emerson on Fri Feb 22, 2019 4:24 PM

Seeing how my mod uses sync signals derived from the console video I assume it will work just fine. We'll find out for sure once I get some boards out to the testers.


Also, I will be designing an 8pin mini DIN pcb with a pinout that matches Fred's mod and the XRGB input.

#4224627 Intellivision ntsc rgb mod design help

Posted by emerson on Thu Feb 21, 2019 5:17 PM

Just got another person on board to test my mod with their framemeister.

#4224504 Intellivision ntsc rgb mod design help

Posted by emerson on Thu Feb 21, 2019 2:13 PM

The video scaler arrived today. In short order I had the intellivision -> scart cable -> scaler -> hdmi monitor setup working. The scart cable is some generic one I bought off ebay to demonstrate my mod is compatible with Genesis 2 rgb cables. Pulling one of the V1-V4 wires verifies the scaler is processing rgb and not composite video. The picture quality is better than in the photos below but is still not super sharp. The scart cable is neither 75 ohms or ground shielded so that is the first thing I want to try changing. It's also a cheap scaler so it could just be that. Either way I'm happy that my mod works with standard unmodified equipment.


I am looking for an Intellivision 2 to do more testing. If you have one and would like to sell/trade it, send me a pm and we'll work something out. I have someone lined up to test my mod on their OSSC, but if you have a different scaler and would like to test let me know. Thanks!


The setup



800x600 resolution



Notice the haziness between the letters in 800x600 mode



1280x720 resolution



There is less haziness



#4220636 Intellivision ntsc rgb mod design help

Posted by emerson on Fri Feb 15, 2019 5:55 PM

I've got both boards designed and built. I'm pretty happy with how everything looks so I will be ordering some professionally made boards in the near future. I think I will change the necessary through-hole pads to SMD to make the installation process easier. The expansion pads will remain through-hole so the end user can solder pin headers in and connect their expansion boards arduino shield style.


I decided to add composite video to the dsub 15 board. The end user can decide to not populate the LM1881 (and a few passives) and jumper composite video on pin 13, or populate all components and have c-sync on pin 13 and v-sync on pin 14. The picture below shows everything populated. The female pin headers are there just for testing purposes.




#4216905 Intellivision ntsc rgb mod design help

Posted by emerson on Sun Feb 10, 2019 7:46 AM

There are a few details I should have mentioned before:

   - The 3.5mm audio jack is optional for this board and you can get stereo audio from the mini din9 connector.

   - The top of the pcb is a giant ground shield to help eliminate interference.

   - Cutting off the 12v leg will not affect any other part of the circuit.

#4216555 Intellivision ntsc rgb mod design help

Posted by emerson on Sat Feb 9, 2019 3:18 PM

The soldering did take a few hours with a pencil iron and thin solder. It's a little ugly because I had to pull the parts from the old board and most of the SMD parts still had solder on them. And yes, the channel switch still swaps the palette.

#4216116 Intellivision ntsc rgb mod design help

Posted by emerson on Fri Feb 8, 2019 9:14 PM

Success! I now have a working prototype for the mini din9 board. When I was creating the footprint for the mini din9 connector I was measuring the pins from the bottom but assigning pin numbers from the top, therefore reversing the pinout and rendering my first board useless. Well, it actually worked fine, it just didn't follow the Sega Genesis model 2 pinout.


However, my second board works well. Currently there are female pin headers where the wires will be soldered. That allows me to work on the board without having to desolder a bunch of stuff. I decided to omit the voltage regulator and just pull +5v from the mainboard, it just runs too hot. Below are some pictures of the board and a staged install. I don't want to solder it in until I make the dsub 15 board.


I should receive the scart to hdmi scaler I ordered in about a week or so and just received my Genesis model 2 rgb scart cable, so I will post some pictures of that when it arrives to demonstrate sega pinout compatibility. I will also post pictures of the dsub 15 board when I get that built. Once I'm comfortable with both boards I will have them made professionally then begin work on the mod instructions.


The ptototype



Top side



Bottom side



The alignment is almost perfect!



The black line on the left will cut off the +12v leg


#4213418 screen memory

Posted by emerson on Tue Feb 5, 2019 7:55 AM

You could limit each room to 8 interactive objects and dedicate an object status variable to each room.
Dedicate another variable to door status for 4 rooms, and toggle bits when items are hit or doors are opened/closed.
Keep all of the coordinate data in tables.

Assuming 50 rooms, 50 object vars + (50/4) door vars = 63 8-bit variables


If you were to limit the amount of rooms to 40 or 45, you could pack each room into its own 16-bit variable.

This allows you to add more doors and items to each room while leaving a couple 16-bit variables for other uses.


Example code:


#4209221 Intellivision ntsc rgb mod design help

Posted by emerson on Wed Jan 30, 2019 12:43 PM

A quick update. I've finalized the pcb design and am ready to make some prototypes. I decided to make two different circuit boards based on the needs of the end user. Some of the features include:


   - either mini din9 (RGB + C video) or dsub15 + 3.5mm audio out (rgb only) for AV output

   - stereo audio with optional blend knob and/or dual mono switch

   - the channel switch selects between two different palettes

   - optional switch to select either TTL or attenuated composite sync signal (stripped from composite video via LM1881)

   - optional switch to select the 0.015uF capacitor in the solarfox composite video circuit

   - all unused pins of the GAL22V10 are connected to solder pads for end user development


Parts are in the mail now and I will give another update once I get things working.

#4203814 Intellivision ntsc rgb mod design help

Posted by emerson on Tue Jan 22, 2019 9:01 PM

Nice work! If you can plug that SCART cable into a Sega Genesis model 2 and it works then the cable will be compatible with my mod as well.


As far as palette switching goes, the two default palettes will be the standard NTSC palette and a palette with colors that better match what they're called in the datasheet. The palettes are switchable with the channel switch and if you have a TL866 programmer you can download WinCUPL and create your own palettes. I think it would be cool to have a collection of palettes created by everyone uploaded here. Then people could pick which they like best and update their firmware.


I'm putting the finishing touches on the pcb now so hopefully I can get in the garage soon and make a prototype board.

#4202524 Intellivision ntsc rgb mod design help

Posted by emerson on Mon Jan 21, 2019 11:26 AM

This is my first RGB console mod truth be told, and I only modded my Trinitron so I would work on projects like this and learn more about RGB.