Duewester Posted May 22, 2023 Share Posted May 22, 2023 10 hours ago, Hans23 said: Diodes with a really low forward voltage drop are only available in SMD packages, but the Vishay/Diodes Incorporated SB110 has 0.48 Volts which should be OK. The TN9k uses a TMI7003C voltage regulator, but the data sheet is not clear on how much higher the input voltage must be in order for the output voltage to be stable. 3.9V->3.3V might be OK, but 4.5V->3.3V surely is on the safe side. I've got some 1n5817 Schottky diodes. Would that work? Quote Link to comment Share on other sites More sharing options...
retrocanada76 Posted May 22, 2023 Author Share Posted May 22, 2023 6 minutes ago, Duewester said: I've got some 1n5817 Schottky diodes. Would that work? it should work 1 Quote Link to comment Share on other sites More sharing options...
+5-11under Posted May 22, 2023 Share Posted May 22, 2023 Just curious... with the diode attached... are you powering the FPGA separately from the TI? Edit: or is the FPGA getting power from the HDMI? Quote Link to comment Share on other sites More sharing options...
Duewester Posted May 22, 2023 Share Posted May 22, 2023 (edited) @retrocanada76, @Hans23, Installed 1N5817 Hooked up HDMI to installed F18aTang. Turned on TV. Turned on TI. Beep, beep, pause, - Normal Ti startup. Cycled Ti with long and short pauses between cycles. Two beeps and a pause. Hooked up my flat jumper and repeated power up and power cycle. ALL GOOD. Hooked up VGA with HDMI still connected - powered up GOOD. Two screens. Cycled power several times - ALL GOOD. What's next? Edited May 22, 2023 by Duewester 1 Quote Link to comment Share on other sites More sharing options...
Duewester Posted May 22, 2023 Share Posted May 22, 2023 The set up 1 Quote Link to comment Share on other sites More sharing options...
retrocanada76 Posted May 22, 2023 Author Share Posted May 22, 2023 52 minutes ago, Duewester said: @retrocanada76, @Hans23, Installed 1N5817 Hooked up HDMI to installed F18aTang. Turned on TV. Turned on TI. Beep, beep, pause, - Normal Ti startup. Cycled Ti with long and short pauses between cycles. Two beeps and a pause. Hooked up my flat jumper and repeated power up and power cycle. ALL GOOD. Hooked up VGA with HDMI still connected - powered up GOOD. Two screens. Cycled power several times - ALL GOOD. What's next? well it's working now ? enjoy are you able to test the fancy feature like the super mario ti99 ? I am curious how do the look like. My nabu the short cycle must be at least one second with the hdmi on. Quote Link to comment Share on other sites More sharing options...
retrocanada76 Posted May 22, 2023 Author Share Posted May 22, 2023 1 hour ago, 5-11under said: Just curious... with the diode attached... are you powering the FPGA separately from the TI? Edit: or is the FPGA getting power from the HDMI? There is no aux power, the TI powers up the tang but not vice-versa the diode prevents the tang to power up the PC and moving the CPU since the VCC lines are connected. The power from the HDMI EDID line is not enough to power on the Tang but is able to put the 9900 to work with everything else not powered yet. 1 Quote Link to comment Share on other sites More sharing options...
retrocanada76 Posted May 22, 2023 Author Share Posted May 22, 2023 50 minutes ago, Duewester said: The set up looking good If you think that you have left out of the fun now, the quality of the colors on VGA is the choice of resistors. Ideally the choice would be: 500 1K 2K 4K but using through the hole we don't get 500 or 4K commercially. But we could do it instead, since you can easily by 1K and 2K resistors: use 2x 1K in parallel for the 500, and 2x in series for the 4K. Make a new VGA breaker and compare Maybe we need pulldowns for the outputs for an even better display. The impedance on the cable is 75 Ohms. I am not sure how much the pulldown should be in this case. If you look at mister IO board it uses the same R (i guess is 1K) value but doing in parallel and in series to reach the bit values and at the end it does the same value R as pulldown. I think in our case it would be 1K as well ? That's it if you want some fun... Quote Link to comment Share on other sites More sharing options...
Duewester Posted May 22, 2023 Share Posted May 22, 2023 I have to put it all together first. I have several things to try on it. Wanna make sure my TiPi/32k still works. Need to verify the Tipi Final from is working. This is my homemade keyboard and I gotta make sure I didn't fudge it up ( the wiring and keyboard breakouts are a little tenuous). Been working on a amplified audio output for a Ti withe F18aMk1 on it. Now I need two. Made my own joystick (visible on top of other Ti in picture) and I want to try it. FG99 has lots of games but I don't know about Super Mario. Since I have the VGA board on the outside, it should be easy to play with the colors. I have a bunch of small variable resistors of a wide variety. Maybe do some fine tuning... Quote Link to comment Share on other sites More sharing options...
craftsman1234 Posted May 22, 2023 Share Posted May 22, 2023 On 5/1/2023 at 7:52 AM, retrocanada76 said: Sharing my latest project I've been working recently: Great work. Just wanted to let you know got all the parts finally on Friday and got it all built for my NABU. Really cool. I do have one question on first power up the F18 screen pops up and nothing after that. You can press reset and runs fine after that. Is this normal? Thanks again for doing this. Quote Link to comment Share on other sites More sharing options...
retrocanada76 Posted May 22, 2023 Author Share Posted May 22, 2023 30 minutes ago, craftsman1234 said: Great work. Just wanted to let you know got all the parts finally on Friday and got it all built for my NABU. Really cool. I do have one question on first power up the F18 screen pops up and nothing after that. You can press reset and runs fine after that. Is this normal? Thanks again for doing this. it's the missing diode. I am updating the board now. but you can easily modify and install a 1N5817 or a 1N4001 between the VCC from the TMS to the VCC on the Tang. Cut the trace and place a diode there. The cathode goes to the tang. btw did you update the github ? I had updated the code it might be even working without diode on the nabu. Quote Link to comment Share on other sites More sharing options...
craftsman1234 Posted May 22, 2023 Share Posted May 22, 2023 2 minutes ago, retrocanada76 said: it's the missing diode. I am updating the board now. but you can easily modify and install a 1N5817 or a 1N4001 between the VCC from the TMS to the VCC on the Tang. Cut the trace and place a diode there. The cathode goes to the tang. btw did you update the github ? I had updated the code it might be even working without diode on the nabu. Quote Link to comment Share on other sites More sharing options...
craftsman1234 Posted May 22, 2023 Share Posted May 22, 2023 I was wondering if it was that. I could see that the HDMI was powering the FPGA. I checked the github just over an hour ago and download the file and programed it into the 2nd Tang. It showed 1.9 which is what I installed 2 days ago. What version is the new one? EDIT Just read the file and see today is different then what I downloaded Friday. I'll check further and let you know. Quote Link to comment Share on other sites More sharing options...
craftsman1234 Posted May 22, 2023 Share Posted May 22, 2023 22 hours ago, retrocanada76 said: so @Duewester as a quick fix for your fat board, cut the green mark (blue trace under the board) and put a diode 1n4001 between these pins as shown: Hi can you post a picture of the mod for the original board I have in the NABU. Quote Link to comment Share on other sites More sharing options...
craftsman1234 Posted May 22, 2023 Share Posted May 22, 2023 23 minutes ago, craftsman1234 said: Updated the Tang in the Nabu. The version online has this date, Sun May 21 12:16:14 2023. No difference in the boot screen going away. Quote Link to comment Share on other sites More sharing options...
retrocanada76 Posted May 22, 2023 Author Share Posted May 22, 2023 I had to solder on the pin base of the TMS connector pins, under the board: Quote Link to comment Share on other sites More sharing options...
retrocanada76 Posted May 22, 2023 Author Share Posted May 22, 2023 the trace is on the front, cut it and then under you connect the diode Quote Link to comment Share on other sites More sharing options...
retrocanada76 Posted May 23, 2023 Author Share Posted May 23, 2023 a new board has been updated to the repo if you want a new one. Quote Link to comment Share on other sites More sharing options...
jltursan Posted May 23, 2023 Share Posted May 23, 2023 This thread is a really good reading, thanks to all involved! 👏 Now, does anyone have plans to build the compact version and make it available to purchase?, Hans? Quote Link to comment Share on other sites More sharing options...
craftsman1234 Posted May 23, 2023 Share Posted May 23, 2023 16 hours ago, retrocanada76 said: the trace is on the front, cut it and then under you connect the diode Thanks. I'll give it a go. Need to order the diode. Have you tested this mod with a NABU? Quote Link to comment Share on other sites More sharing options...
retrocanada76 Posted May 23, 2023 Author Share Posted May 23, 2023 2 minutes ago, craftsman1234 said: Thanks. I'll give it a go. Need to order the diode. Have you tested this mod with a NABU? yes where i tested it i don't have a ti99 yet Quote Link to comment Share on other sites More sharing options...
Artoj Posted May 23, 2023 Share Posted May 23, 2023 Thanks for your good work retrocanada76, I have been working on a VDP replacement for a while and this one hit the jackpot!! Using a Tang was a stroke of genius, here is my version 3 without surface mount. Regards Arto Quote Link to comment Share on other sites More sharing options...
retrocanada76 Posted May 23, 2023 Author Share Posted May 23, 2023 I can confirm that I got much better colors using 500, 1k, 2k and 4k. Maybe using 1K and 2K resistor arrays would be a solution. I tested on my CX5M. Quote Link to comment Share on other sites More sharing options...
Hans23 Posted May 23, 2023 Share Posted May 23, 2023 5 hours ago, jltursan said: Now, does anyone have plans to build the compact version and make it available to purchase?, Hans? I have a couple of boards that I can pass on. If you're interested, put yourself onto my waiting list. 4 Quote Link to comment Share on other sites More sharing options...
retrocanada76 Posted May 23, 2023 Author Share Posted May 23, 2023 3 hours ago, Artoj said: Thanks for your good work retrocanada76, I have been working on a VDP replacement for a while and this one hit the jackpot!! Using a Tang was a stroke of genius, here is my version 3 without surface mount. Regards Arto But the Tang cannot read 5V. This is why I was using 3x 74VLC245 to lower it down to 3.3v Quote Link to comment Share on other sites More sharing options...
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