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My Dragon 32 that I bought broken on eBay showed this screen pattern. I thought it was the 6847 but it turned out to be a poor -5V supply. The culprit was the capacitor C5 on the power board, the one between the R5 resistor which gets pretty warm and the row of power diodes. Make sure you get the po...

The way I understand the tokenization and parsing you don't need spaces anywhere.

Does anyone know if a trs-80 color computer disk controller will work without modification in a Dragon 32? You'll need to replace the controller ROM with a DOS that integrates with Dragon BASIC and is compatible with the disk controller. HDB-DOS for Dragon should work, as well as the SuperDOS porte...

When you measured that all keys worked as they should, did you measure directly on the PIA pins? If you're into a bit of coding you could try checking the PIA by writing to the PIA port B and measure that it outputs the right values. And you can connect port A pins to low and high (without pressing ...

The best reference for these things are Graham's files at http://dragon32.info/info/

Thanks, first time I see the inside of a Dragon power brick! So was there a fuse in there? That question came up in another thread.

Hi all - I'm tinkering with some old code I wrote some 30 years ago. It's an extension to basic, so I need it to behave nicely. It loads from $7000 upwards, but back in the day, I didn't want people to have to do a "CLEAR 100,&H6FFF" before loading (I wanted to make it easy), so I did it for them. ...

When using machine code you are not limited to two pages. The SAM has a 7-bit register which (multiplied by 512) defines the start address of the displayed graphics. The graphics mode defines the length of the video memory region. There are a number of books that explain this well, for instance "Ins...

I don't see -gdb on your command line?

Well, for anything music on CoCo/Dragon it is worth checking out Bill Pierce's stuff... :) The ORCH.BIN code being outside the cartridge area should make it easier to combine with a real DOS. It would be very nice if it used disk access routine vectors instead of poking the disk controller. Actually...