Search found 7 matches

by River-of-Dust
27 Jun 2022, 03:59
Forum: Support
Topic: Not functional; Blinkenlights static
Replies: 12
Views: 431

Re: Not functional; Blinkenlights static

5) Okay, I found time to test the resistors, and I measured the following (all okay, basically): R1 = 0.997M R2 = 1.004K R3 = 2.218K R6 = 2.216K R7 = 2.218K R10 = 2.195K R19 = 2.211K Now, I'll need to find the time to write a sketch for my Arduino Mega (well, Keyestudio Mega Plus, but same thing) to...
by River-of-Dust
22 Jun 2022, 08:07
Forum: Support
Topic: Not functional; Blinkenlights static
Replies: 12
Views: 431

Re: Not functional; Blinkenlights static

Thanks! Here's what I've found time for so far: 1) I ordered another oscilloscope probe and finally got some time to try it out. I captured the attached pictures when the probes and scope were all set to 10x. (I'm still new to using an oscilloscope, and I'm still puzzled why the ground wires of near...
by River-of-Dust
15 Jun 2022, 00:39
Forum: Support
Topic: Not functional; Blinkenlights static
Replies: 12
Views: 431

Re: Not functional; Blinkenlights static

Oh, and that last scope capture was of U3 pin 11, I believe. Looks like my camera caught it just as the signal was jumping a bit. It was mostly stable, but it did jump around a little bit, as if the signal was changing in some way. Staying on a 1 or a 0 longer, I guess. -Derek Need to head out so I'...
by River-of-Dust
13 Jun 2022, 04:42
Forum: Support
Topic: Not functional; Blinkenlights static
Replies: 12
Views: 431

Re: Not functional; Blinkenlights static

Need to head out so I'll keep this short. Refer to page 3 of the Gigatron schematic. Are you comfortable pulling U1 and connecting CLK1 (output)/RST_B (input)/PL_B (input)/PH_B (input)/PC[15:0] (input) to your Arduino and single step through the entire PC incrementing per https://raw.githubusercont...
by River-of-Dust
12 Jun 2022, 09:57
Forum: Support
Topic: Not functional; Blinkenlights static
Replies: 12
Views: 431

Re: Not functional; Blinkenlights static

1) You're going to want to look at the clock visually on an oscilloscope to make sure it has the right voltage levels and a monotonic rising edge. Do you have access to one? 2) If you're measuring 5V at U3-11, I was hoping that meant PC3 was stuck high. It's not clear to me if your Gigatron is just...
by River-of-Dust
11 Jun 2022, 04:27
Forum: Support
Topic: Not functional; Blinkenlights static
Replies: 12
Views: 431

Re: Not functional; Blinkenlights static

Good job listing all the debug you've done. A couple of things jumped out at me. Can you confirm:- 1) when you say the clock ticks at the right freq, are you measuring both CLK1 and CLK2 with an oscilloscope? 2) can you check (again) if there might be a short between U3-10 and U3-11? 3) do you have...
by River-of-Dust
10 Jun 2022, 12:04
Forum: Support
Topic: Not functional; Blinkenlights static
Replies: 12
Views: 431

Not functional; Blinkenlights static

Hello! I'm hoping someone can help me with this, because I've been trying to troubleshoot it on my own for a few weeks on and off with no luck. :-( I ordered a set of boards from a Tindie vendor, ordered the parts I didn't already have from Digi-Key, Mouser, etc, and put it all together. The power l...