greg@dekalb.UUCP (Greg Philmon) (04/28/89)
A friend wants me to upgrade his Tandy 1000 (SL?) from 384 K to 640 K. Fine.
All I need is a bank of 41256-15, right?
Now I'm not so sure. Knowing a little of Tandy's reputation for (non)
compatibles, I decided to give them a call. Here's what I learned, more
or less in order:
1) No, you can't use 256 K chips - you need 128 K chips. Well, I had never
heard of that, so called my chip supplier. Yup - they exist. So I'll
go ahead and get them.
2) Called another RS Compter Center. Nope. You don't use 128 K chips -
you need two banks of 64x4 chips (4464) Huh? I was under the impression
that this was used only in video cards. Plus, two banks of these would
be 512 K - I only need half that.
3) <sigh> Yet another call to Tandy - this time to their (not toll-free)
"Hot-line". Yup - I need two banks of 4464 chips. "That'd be eight
chips, total." Okay, fine. No parity and some kinda screwed up
RAM setup. But I can still do it for about 1/2 of tandy's price.
Is some (any) of the above on track? I haven't had a chance to actually
open his machine and look, but really doubt that it uses 64x4 chips for
the main memory.
I'd appreciate any help you can give.
--
---------------------------------------------------------
| Greg Philmon ...gatech!dekalb!greg CIS: 72261,1724 |
---------------------------------------------------------ugkamins@sunybcs.uucp (John Kaminski) (04/30/89)
In article <485@dekalb.UUCP> greg@dekalb.UUCP (Greg Philmon) writes:
=>A friend wants me to upgrade his Tandy 1000 (SL?) from 384 K to 640 K. Fine.
=>All I need is a bank of 41256-15, right?
=>
=>Now I'm not so sure. Knowing a little of Tandy's reputation for (non)
=>compatibles, I decided to give them a call. Here's what I learned, more
=>or less in order:
=>
=>1) No, you can't use 256 K chips - you need 128 K chips. Well, I had never
=> heard of that, so called my chip supplier. Yup - they exist. So I'll
=> go ahead and get them.
=>
=>2) Called another RS Compter Center. Nope. You don't use 128 K chips -
=> you need two banks of 64x4 chips (4464) Huh? I was under the impression
=> that this was used only in video cards. Plus, two banks of these would
=> be 512 K - I only need half that.
=>
=>3) <sigh> Yet another call to Tandy - this time to their (not toll-free)
=> "Hot-line". Yup - I need two banks of 4464 chips. "That'd be eight
=> chips, total." Okay, fine. No parity and some kinda screwed up
=> RAM setup. But I can still do it for about 1/2 of tandy's price.
=>
=>Is some (any) of the above on track? I haven't had a chance to actually
=>open his machine and look, but really doubt that it uses 64x4 chips for
=>the main memory.
=>
=>I'd appreciate any help you can give.
=>--
=> ---------------------------------------------------------
=> | Greg Philmon ...gatech!dekalb!greg CIS: 72261,1724 |
=> ---------------------------------------------------------
Yeah.........? So what's so wrong with using 2 chips for 64K of memory? You
have 1 chip for the upper nybble and 1 chip for the lower nybble. Don't worry,
be happy that it will work. There's really no problem there, it's just a
little different. I'd also like to see the sockets use one bit wide chips,
but they aren't. Oh well.....garyk@techsup.UUCP (04/30/89)
> /* Written Apr 28, 1989 by dekalb.UUCP!greg in techsup:comp.sys.tandy */ > /* ---------- "Tandy RAM upgrade" ---------- */ > A friend wants me to upgrade his Tandy 1000 (SL?) from 384 K to 640 K. Fine. > I decided to give them a call. Here's what I learned, more or less in order: > > 3) <sigh> Yet another call to Tandy - this time to their (not toll-free) > "Hot-line". Yup - I need two banks of 4464 chips. "That'd be eight > chips, total." Okay, fine. Yes, the correct answer is #3! But they all do a really nice memory test on power up!! 4464s would allow a stop at 512K if you only used 4 chips. (but that is not supported). This is ONLY true of the 1000SL, BE SURE it is a 1000SL! A quick test is 256K x 1 RAMs use 16 pin IC sockets. 64K x 4 RAMs use more pins (18 pins off the top of my head). I do not recall the acess time required, i think 120ns would be fine (if not expensive). Use the speed of the RAMs in the bank next to the empty sockets as a guide. > No parity and some kinda screwed up > RAM setup. But I can still do it for about 1/2 of tandy's price. None of the 1000 series has used parity. Screwed up is relative. I thought the 8088 was screwed up compared to the 68000. Although i am beginning to like the '386. As a note, the SL uses a 8086. > > Is some (any) of the above on track? I haven't had a chance to actually > open his machine and look, but really doubt that it uses 64x4 chips for > the main memory. Use the above & look inside if you still have questions. Also the Technical Reference manual for the computer is available from Tandy. It provides some techie info, schematics, and a parts list. > --------------------------------------------------------- > | Greg Philmon ...gatech!dekalb!greg CIS: 72261,1724 | > --------------------------------------------------------- > /* End of text from techsup:comp.sys.tandy */ Gary Kueck techsup!garyk