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SRAM for MuP21 development systems


On Tue, 15 Nov 1994, Jeff Fox wrote:

> MuP21 is in a 40-pin DIP package.  Single unit price is $25, available
> immediately from Offete Enterpriese.  A MuP21 Development System ($350) is
> available for software developers.  It includes a small PC board with a MuP21
> chip, 2.5 Mbytes of fast DRAM, an 128-Kbyte EPROM with boot and demo programs. 
> A suite of assembler and utilities is supplied to help the user developing
> applications on PC under DOS.  An unassembled kit (MuP21, a printed circuit
> board, an 128K EPROM, software and documentation) is also available for
> hobbists at $100. 

I din't see the development system to include SRAM. I know, that 
execution speed off SRAM and DRAM is comparable due to long memory setup 
time of the processor itself. SRAM would help a lot, though, to reduce 
the number of off-page memory accesses, forced by the video generation. 
So, to get the full speed, one has either disable video generation and 
refresh (while guaranteeng, that the data access pattern of the 
computation will refresh the meory,) or execute the time-critical code 
off SRAM.

Does the system include SRAM?
If not, does it allow for the user to add SRAM easily?

> 4012  	MuP21 Development System, $350
> MuP21 system with 1Mx20 DRAM, 128KB EPROM, parallel I/O port, in an attractive
> box.  Apply 5V power and it generates NTSC signals to drive a color TV monitor.
> MuP21 assembler and sample code included to guide application development.


--
Penio Penev <Penev@venezia.Rockefeller.edu> 1-212-327-7423