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YM2151 Sound

1 minute read

Getting the sound working turned out to be easier than expected and managed to get the YM2151 playing music fairly quickly. To get some music playing I used...

Monitor ROM

less than 1 minute read

Y Ddraig now has a ROM based monitor program to speed up development and debugging. It’s based on the zBug monitor by Wichit Sirichote. The ability to...

It’s Alive

1 minute read

A working serial port! Tracking down the problem Fixing this involved a bit of head-scratching when trying to track down the problem. All logic signa...

First Software

4 minute read

With the hardware assembled and the CPLD programmed it’s time to start writing some code to test and see if the hardware is working. The first program to te...

Address decoding

3 minute read

Before writing any software for Y Ddraig the CPLD will need to be programmed. The CPLD being used here is a Xilinx XC95108 and it is responsible for the addr...