Dead AIM 65??

On 4/14/05, Tony Duell <ard at p850ug1.demon.co.uk> wrote: That's OK... I have a couple and can fill in gaps. Perhaps one of the later models, but every one I've seen has a set of 5 4-char ASCII LED modules driven by a 6520 (6821). +5VDC only. The +24V is for the thermal printer. I mentioned the usefulness of a logic probe in an offline message. If one doesn't have an o-scope to watch clocks, enables, etc., at least a logic probe will reveal some of the show stoppers (missing clock, missing RAM enables, etc.) I also mentioned to swap the RAM around in case one of the 2114s for the zero page has failed. 6502s do _not_ like errors in zero page or in the stack. Quite unforgiving. Other than the printer and the ASCII displays, there's nothing remarkable about the AIM-65 compared to any other 6502 SBC. It's SRAM, so there's no -ve supply voltages to worry about (like with 4116 DRAMs) and no refresh circuit to debug. The downside is that there's only room on the mainboard for 4K, so memory expansions are external, and used to cost a lot (and are rare now because there didn't use to be a wide variety of them). For those unfamiliar with the model, it was Rockwell's answer to the KIM and SYM, and was frequently found in a metal-bottomed, vacuformed-topped case, unlike the KIM and SYM which were frequently found as bare boards. The AIM-65 had BASIC as a rather common option (don't remember if it was always present), and routinely came with a full-sized ASCII keyboard to complement the hardcopy and/or ASCII LEDs. It's pretty useful out of the box for a machine that doesn't come with a disk interface. You certainly get more than the few digits and a calculator keypad of the KIM/SYM line. -ethan