#18 - VDA, VPA and RD/WR rework - BB816 Computer
Become a Patron: / adrienkohlbecker
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In this video, I describe the VDA and VPA pins of the CPU, and generate new signals for valid addresses and opcode fetches. After adding them to the monitor, I then discuss a few updates we have to make to the read and write pulses: VA, BE and RDY support. I design a new circuit for them and analyze its timings.
Join me in discussing this project in the 6502 forums: http://forum.6502.org/viewtopic.php?f...
View the source code and schematics shown in this video: https://github.com/adrienkohlbecker/B...
The most recent source code and schematics are available here: https://github.com/adrienkohlbecker/B...
Chapters:
00:00 Intro
00:22 VDA, VPA pin description
03:07 Adding VA, SYNC to KiCad
06:02 Breadboard implementation
07:44 Updating Arduino Monitor
09:29 Updating RD, WR
17:07 KiCad implementation
19:41 Timing diagrams
24:34 Outro