Zilog z80 to Motorola 6809 Transcode – Part 010 – Fixed IRQ interfering with character rendering

Well I figured out the problem with the characters not being displayed correctly.  It was a problem with the Interrupt.  While in regular mode the code was displaying the text characters and at the same time the IRQ would print CREDITS 0 over and over and if they hit at the same time the IRQ changed some screen pointers and blamo crappy text.

With the text problem fixed I also battled the different coloured ghosts and it looks pretty cool now.


The next part of the attract mode is Pac man moving across the screen being chased by the ghosts.  This is done with sprites and it’s the next thing I will be working on…

See you in the next post…

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