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Building a Klyball 470K

Posted: Tue Apr 02, 2019 3:39 am
by Jeff
To add memory and floppies to my C4P replica build, described here: viewtopic.php?f=3&t=413,

I have decided to use the 470K.

This thread will document the board and the build.

In this build, I plan to use the RAM and ROM on the 470K and not use the ROMS and 2114's on the 502 board. Should be interesting!

/Jeff

Re: Building a Klyball 470K

Posted: Tue Apr 02, 2019 3:47 am
by Jeff
Here are photos of the bare board.

Top:
top bare small.jpeg
top bare small.jpeg (338.01 KiB) Viewed 10914 times
Bottom:
bottom bare small.jpeg
bottom bare small.jpeg (341.84 KiB) Viewed 10914 times
/Jeff

Re: Building a Klyball 470K

Posted: Tue Apr 02, 2019 3:51 am
by Jeff
Here is the current parts layout.... It is a work in progress and I will upload updates as they happen.
Parts Layout small.jpeg
Parts Layout small.jpeg (1.46 MiB) Viewed 10914 times
/Jeff

Re: Building a Klyball 470K

Posted: Tue Apr 02, 2019 3:57 am
by Jeff
Progress so far...
470 progress.jpeg
470 progress.jpeg (578.31 KiB) Viewed 10913 times
/Jeff

Re: Building a Klyball 470K

Posted: Fri Apr 26, 2019 10:58 pm
by Jeff
More parts added. just missing a few caps.
470z.jpg
470z.jpg (523.15 KiB) Viewed 10715 times
/Jeff

Re: Building a Klyball 470K

Posted: Tue Apr 30, 2019 1:02 am
by Jeff
I double-checked my work.

I discovered that the 500 0.1uf caps I bought (probably from china) weren't actually 0.1uf. They had a part number of 104 on them, which should be 0.1uf, but when I tested them, (and I tested many of them!) they measured 0.05uf! So I had to de-solder them all and install correct ones. I have now adopted a policy of testing my parts before installing them.

Here is the board so far. I am only missing one capacitor now. You will notice that all the little orange caps have been replaced with tan coloured ones.
470z.png
470z.png (1.56 MiB) Viewed 10654 times
/Jeff

Re: Building a Klyball 470K

Posted: Mon Sep 09, 2019 11:24 pm
by Jeff
I have populated just enough of the board to add memory to the system. There is 4K on the 502, and I programmed the GAL on the 470K to extend the ram to 40K (just below BASIC IN ROM)
40K Screen.jpg
40K Screen.jpg (616.95 KiB) Viewed 9563 times
Here is a photo of the board so far.
470z Progress - 40K RAM.jpg
470z Progress - 40K RAM.jpg (1.16 MiB) Viewed 9563 times
/Jeff

Re: Building a Klyball 470K

Posted: Wed May 20, 2020 4:25 pm
by Jeff
Just a note, that I haven't forgotten this project, but I have been busy with other things.

/Jeff