New Chip, Great Idea

[Craig Pugsley]

> 
> I got some information on a new chip, this is a great idea for those of 
> you who design stuff that uses a HC11 or 8051 and need more ports and 
> less board space used.
> 
> The chips are the "PSD" family. They contain Eprom, RAM, address decode 
> logic, ports and such. Most of the stuff you normaly have as seperate 
> chips. The chip has a window for erase of the Eprom.
> 
> They have many models, so you should ask for the information sheets they 
> have.

Any part numbers? (I want to look on our CD rom)

Also of similar description is the Xicor 88C64, which is an 8k EEPROM
specifically designed as a 'single chip memory for single chip micros'.

It has the following features:
-8k (Flash?) EEPROM
-Memory can be segmented into multiples of 1k, and designated as
 program memory or data memory (Important for some chips as these
 address ranges overlap/are the same)
-10,000+ write cycles (Needs no special voltages to write to chip)
-'Data protection': You must a 3 byte sequence before a write, this
 stops rogue processors from killing everything in the memory
-'Write protect' of any of the 1k blocks (EG write protect the program)
-'Dual plane architecture' - allows you to continue reading after a
 write is initiated (As a write takes a few mS to finish)
-No 'glue logic' required for 8051 family or 68HC11 family, all
 latches etc on chip.

This chip seems just about perfect for DIY_EFI memory, however I don't
know if it's available in larger sizes.
Price (in australia) is around $US20 (incl.tax.) for 1 offs., which is
still a bit cheaper than an EPROM and a RAM with extra board space etc.

I thought I might put the serial download code in the first 1k, and
write protect it, then put the downloaded code into 4k, and data in the
last 3k. But first I'm getting my basic setup with eprom and sram going.

Craig.
pugsley at trl.oz.au