Post Reply 
Keycodes: SR-52 vs TI-58/59
12-18-2022, 04:40 AM
Post: #1
Keycodes: SR-52 vs TI-58/59
Hi.

TI went from four steps to three for transfer instructions and from three strokes to two for memory instructions. What technology and memory chips would it have taken for 58/59 keycodes in the SR-52 to begin with?
Find all posts by this user
Quote this message in a reply
12-18-2022, 05:58 AM (This post was last modified: 12-18-2022 06:02 AM by brouhaha.)
Post: #2
RE: Keycodes: SR-52 vs TI-58/59
It's essentially the same reasons the HP-65 wasn't as powerful as the HP-67, which wasn't as powerful as the HP-41, and so on.

The same chipset (TMC0501 etc.) Is used in the SR-52 and TI-58/59, but the SR-52 has only 3K (13-bit words) of ROM, vs. 6K in the TI 58/59. For the TI-58/59, there were the same number of ROM chips in the calculator, but by that time they could make 2.5K ROM chips, vs. only 1K when the SR-52 was designed, so it would have taken twice as many ROM chips, as well as delaying the introduction of the SR-52 by the time needed to write and debug twice as much code.

As Bill Wickes of HP famously observed some years later, "ROM wasn't built in a day."
Find all posts by this user
Quote this message in a reply
Post Reply 




User(s) browsing this thread: 1 Guest(s)