LED Speed Display Settings for my 386? \ VOGONS

LED Speed Display Settings for my 386?

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First post, by zuldan

Posted on 2024-01-07, 06:32

zuldan Offline

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About to finish my 386 build. Just need to configure the LED Speed 40/25. I've had a look at https://www.minuszerodegrees.net/led_speed_di … eed_display.htm but can't find a PCB that matches. Is it just a process of elimination to figure out the settings? Can I assume top row is turbo on and bottom is turbo off (or visa versa). Any tips would be greatly appreciated 😀 It's currently showing "90".

Reply 1 of 5, by BitWrangler

Posted on 2024-01-07, 06:39

BitWrangler Offline

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I think it might be labelled in the conventional manner for 7 segment LEDs, thus...
https://www.jameco.com/Jameco/workshop/TechTi … t-displays.html
With high and low rows, with each digit having it's setting for each segment like A1 A2, B1 B2 etc down the block.

Unicorn herding operations are proceeding, but all the totes of hens teeth and barrels of rocking horse poop give them plenty of hiding spots.

Reply 2 of 5, by wbahnassi

Posted on 2024-01-07, 07:09

wbahnassi Offline

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My recommendation is while you're figuring it out, do NOT remove all jumpers. Keep all jumpers and just focus on one or two at a time. It seems this is one of those turbo displays that shares one resistor for all LEDs, which means it is calibrated to give decent light when typical digits are displayed. If you remove all jumpers then too much current will go through the LED that you're isolating, and it will burn.

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Intel 386 DX-33, Speedstar 24X, SB 1.5, 1x CD
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Reply 3 of 5, by zuldan

Posted on 2024-01-07, 07:12

zuldan Offline

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BitWrangler wrote on 2024-01-07, 06:39:

I think it might be labelled in the conventional manner for 7 segment LEDs, thus...
https://www.jameco.com/Jameco/workshop/TechTi … t-displays.html
With high and low rows, with each digit having it's setting for each segment like A1 A2, B1 B2 etc down the block.

Fantastic, I got it configured. Thank you!

Reply 4 of 5, by zuldan

Posted on 2024-01-07, 07:12

zuldan Offline

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wbahnassi wrote on 2024-01-07, 07:09:

My recommendation is while you're figuring it out, do NOT remove all jumpers. Keep all jumpers and just focus on one or two at a time. It seems this is one of those turbo displays that shares one resistor for all LEDs, which means it is calibrated to give decent light when typical digits are displayed. If you remove all jumpers then too much current will go through the LED that you're isolating, and it will burn.

Thank you for the tip!

Reply 5 of 5, by zuldan

Posted on 2024-01-07, 07:16

zuldan Offline

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Ok silly questions...

Question 1: I push the turbo button (wires connected to "P" and "L" on the PCB) but the LED display doesn't change. Does the LED PCB need to be connected to the motherboard? As in, the motherboard must confirm that it has changed the turbo mode?

Question 2: There is only 1 wire that goes to the motherboard. It's labeled "S" on the PCB. The motherboard obviously has 2 pin header for the turbo switch. How is that going to work? Does only 1 pin need to be connected?

Apologies for the silly questions, it's my first time configuring one of these.

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