Re: v2 Analog - Apple ][ VGA adapter build
Posted: 28 Apr 2023 17:32
@rubber_jonnie when hand soldering caps and resistors I’ve found it’s easy to miss soldering one side properly, they look soldered but aren’t.
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Aside from all the checks I've already done, I have double checked under a microscope and they are all definitely soldered.PhilC wrote: 28 Apr 2023 17:32 @rubber_jonnie when hand soldering caps and resistors I’ve found it’s easy to miss soldering one side properly, they look soldered but aren’t.
I'm using the ATF16V8C PLD's which program fine with a TL866II programmer and work fine.rubber_jonnie wrote: 27 Apr 2023 22:40Which PLD did you plump for in the end? I used PAL61V8's directly soldered and both of mine work just fine.HomeLate wrote: 27 Apr 2023 19:31
PCB's from JLPCB arrived and the parts from Digikey too. I'm half way through soldering one. Tomorrow I'll finish soldering and I'm only waiting for a PLCC20-20-dip adapter to program the PLD.
The 0402 are so small. I lost a few caps while sneezing :roll:
As for the 0402 caps, well and resistors too, I'm sure I lost as many as I soldered...
Thank god for my microscope is all I can say.
If you have a standard Pico with no WiFi, use the 4ns firmware for LC for either Applicard or VGA. The 8ns LC firmware also works, but is a bit slower. AFAIK, if you use the WiFi firmware with LC boards it gets a bit crashy.HomeLate wrote: 03 May 2023 07:03I'm using the ATF16V8C PLD's which program fine with a TL866II programmer and work fine.rubber_jonnie wrote: 27 Apr 2023 22:40
Which PLD did you plump for in the end? I used PAL61V8's directly soldered and both of mine work just fine.
As for the 0402 caps, well and resistors too, I'm sure I lost as many as I soldered...
Thank god for my microscope is all I can say.
But I'm a bit confused which firmware to use: LC, GS of Wifi? I'm using regular PICO's with no Wifi.
Thanks @rubber_jonnie !rubber_jonnie wrote: 03 May 2023 07:47If you have a standard Pico with no WiFi, use the 4ns firmware for LC for either Applicard or VGA. The 8ns LC firmware also works, but is a bit slower. AFAIK, if you use the WiFi firmware with LC boards it gets a bit crashy.HomeLate wrote: 03 May 2023 07:03
I'm using the ATF16V8C PLD's which program fine with a TL866II programmer and work fine.
But I'm a bit confused which firmware to use: LC, GS of Wifi? I'm using regular PICO's with no Wifi.
No worries, be good to see another up and running.
Yep, the 0402s are terrible, but I reckon I could build one from scratch in 2 hours now I have figured out some techniques. One thing I would say is check the level shifter pins very closely, I had some that weren't soldered, and it is super easy to miss bridges on the tiny pins. I used some ultrafine tweezers to push each pin to be sure they were soldered securely before using my multimeter to check for shorts between pins. Be aware SOME are supposed to be connected together.PhilC wrote: 10 May 2023 21:53 And we got this far
IMG_2679.jpeg
I have respect for anyone who can solder these 0402 components, they are a real pain.
It’s going into the ultrasonic cleaner in the morning and then we shall see if it works when I get a mo.
If I had to make another I’d fork the git and redo it with bigger components so they are easier to build.