Re: Why are TI Calcs so inferior?

Subject: Re: Why are TI Calcs so inferior?
From: Jonathan Todd Samuel <jsamuel+@ANDREW.CMU.EDU>
Date: Sun, 17 Nov 1996 13:10:13 -0500
In-Reply-To: <32954992.6446286@news.msu.edu>

Be careful when you're talking about RAM.  MDRAM, SGRAM, WRAM, SDRAM,
VRAM, etc, are all DRAM memory (they use a capacitor to store data and
need to be refreshed). Most of the speed inprovement comes from little
design tricks like allowing reads and writes to the chip at the same
time or using a 128bit wide data bus. Only good old SRAM uses 4
transistors per bit. It's almost certainly still the fastest type of
RAM* (the P6-200's l1 SRAM cache is faster than 5ns). But what's
important for our calculators is that SRAM is battery friendly and
requires no support circuitry (it's ready to connect dircetly to the z80
all by itself).


*By my calculations, the speed of the RAM is not an issue for the
calculators. I got that the ram must be 166ns (or faster) to keep the
6mhz z80 happy. They don't sell any kind of ram that slow.


-Jonathan

References:

From:

Prev: Re: (TI-83) How do I store a formula as text?
Next: Re: Warning!
Index(es):
- Main
- Thread