HD46505 CRT controller chips

[Chuck Guzis]

On 11 Oct 2007 at 16:04, Chris M wrote:

> the 6545 was a close relative of the 6845. IIRC the TI
> PC used it. No clue where to find one though. The
> Rockwell will probably work. They had their own
> version of the Intel 8272/NEC '465 chip. My old ITT
> Xtra XP used the Rockwell version. It went bust and I
> replaced it with the 8272 from my Tandy 2000. It
> worked fine.

The big difference that's important here is that the Hitachi and 
Rockwell chips have a "transparent" refresh mode that allows a nice 
seamless memory share with a 6502.  Set by Register 8, bit 3.  The 
6845 doesn't have this--so it probably won't work.

Cheers,
Chuck