On 06/18/2013 07:38 PM, Jim Brain wrote: > I guess, but dubious. CBM could have just went and stuffed something in > the address map that contradicted the 6821 address space. IN any event, > it was an academic question. Interesting that they sourced a 6821 > instead of just adding a '574/'245 or something simple. Replacing even a single port of a 6821 or a 6522 with TTLs only sounds simple until you think about what this would really mean. I'd say a 6821 or 6522 needs less space on the PCB than even a limited port setup using TTLs in DIP that supports direction change of the data flow. I once thought about what it would take to replace the 6529 (which is VERY simple) used in the 264 series with TTLs and gave up after 5 TTLs. Gerrit Message was sent through the cbm-hackers mailing listReceived on 2013-06-18 19:00:12
Archive generated by hypermail 2.2.0.