bobh@zaphod.UUCP (Bob Harvey) (01/22/91)
I just purchased a 1764 REU and it works just fine with my old C64 and
GEOS 2.0. However, I bought a second-hand C128 a while back and I'd like
to use it instead (primarily in C64 mode with GEOS) because I prefer the
keyboard. The only thing that concerns me is the line on page 3 of the
1764 User's Guide that says "Remember the 1764 was designed only for the 64
and can NOT be used with the Commodore 128."
I'm sure I've seen somewhere either here on the Net or in Transactor magazine
tales of people using a 1764 with a 128. Is the warning in the User's Guide
for electrical reasons or is it just that the 1764 won't work in C128 mode?
(Or is it just a plot to sell more REU's?! |-)
Since I'm confident there are several kind souls out there with the answer
to my query, I'll say "Thanks!!" in advance.
--
R. M. (Bob) Harvey, Corporate Computer Systems Administrator
Develcon Electronics, 856-51 St. E, Saskatoon, SK. Canada, S7K 5C7
"Innovative High-Performance Internetworking Systems"
E-mail: bobh@zaphod.uucp -=- Phone: (306) 931-1390 -=- Fax: (306) 931-1386bhelf@athena.mit.edu (Bill Helfinstine) (01/23/91)
In article <4104@zaphod.UUCP> bobh@zaphod.UUCP (Bob Harvey) writes: >The only thing that concerns me is the line on page 3 of the >1764 User's Guide that says "Remember the 1764 was designed only for the 64 >and can NOT be used with the Commodore 128." >Is the warning in the User's Guide >for electrical reasons or is it just that the 1764 won't work in C128 mode? >(Or is it just a plot to sell more REU's?! |-) That's answer (c). The only difference between the 1700, 1750, and 1764 is the amounts of memory they contain. The only reason that you couldn't use a 1750 on a C-64 is the power supply. The 1764 comes (came?) with a bigger power supply for the 64, so 128 users would be buying a useless hunk of metal and plastic, since it wouldn't even match the power plug on a 128, much less be necessary. As you have also read, probably, you can upgrade a 1764 to 512K, which is what I did and I am using it on my 128 with no problems. Bill Helfinstine bhelf@athena.mit.edu
root@zswamp.fidonet.org (Geoffrey Welsh) (01/25/91)
>From: bhelf@athena.mit.edu (Bill Helfinstine) >The only reason that you couldn't use a 1750 on a C-64 is the >power supply. That's not quite true: the 1750 won't work on all C64s; the 1764 includes a small change to affect the bus timing. However, from a programming point of view, a 1764 is just a 1750 with 256K missing. Even the REU ID bit (0 for the 128K 1700 and 1 for the 512K 1750) reads 1 on a 1764 (which is why you should test manually for the amount of RAM in an REU in stead of trusting the ID bit <sigh>) -- UUCP: watmath!xenitec!zswamp!root | 602-66 Mooregate Crescent Internet: root@zswamp.fidonet.org | Kitchener, Ontario FidoNet: SYSOP, 1:221/171 | N2M 5E6 CANADA Data: (519) 742-8939 | (519) 741-9553 MC Hammer, n. Device used to ensure firm seating of MicroChannel boards Try our new Molson 'C' compiler... it specializes in 'case' statements!