Schematics and description of an acoustic memory (1k byte, Display terminal, 1969)

pichotjm pichotjm at free.fr
Sun Apr 13 09:02:08 CDT 2008


> Jean-Marie Pichot wrote:
>> This display terminal was designed in 1969,  [...]  Remember,
>> in that time, there are no micro-processor, neither RAM chips!

It was just to remind the common design context in 1969. There were some 
registers for computers or military products.
I have many young readers...

> There were RAM chips in 1969.  Most of them stored 16 bits or
> less.  I have not been able to determine when the first 64-bit RAM
> appeared, but it might have occurred by then.

Are they named RAM in databooks? or registers?
I think i have one, 4 bits but without adress decoding. There are 4 register 
selects!

> Examples of RAM chips available in 1969 were the Fairchild U6A903059X
> 8-bit RAM and U6A903359X 16-bit RAM.  The base part numbers were 9030
> and 9033, respectively.  These were part of the CTuL Complementary
> Transistor Logic (CTuL or CTL) family.  Don't get confused by that
> name; these were complementary *bipolar* transistors, not CMOS.  Many
> years later Fairchild reused the CTL abbreviation for something entirely
> different, Current Transistor Logic.
> By the time of the 1972 Fairchild TTL Data Book, the 9033 designation
> was changed to 93433.
>
> The 9030 was used in the KM10 fast memory "option" for the DEC KA10, the
> first PDP-10 processor, designed in 1967.

Interesting!

> For a raster display terminal in 1969, delay line memory was obviously
> more practical than semiconductor memory, since the density of available
> RAM chips was too low.  This started to change in 1970 when Intel
> introduced the 1101 static RAM (256 bit) and the 1103 dynamic RAM
> (1024 bit), though there were initially a lot of reliability problems
> with the latter.

 I have a lot of MK4007 by Mostek. 256x1 i think similar to the 1101 by 
Intel. They are used in the Beryllium board: 
http://pichotjm.free.fr/1975-1980/Beryllium/PICT8117.html

> The next generation of raster display terminals used MOS dynamic
> shift register memory, which was less expensive than RAM.  As far
> as I'm aware, not many display terminal designs used RAM chips before
> 1977, and MOS shift registers were still being sold into the mid 1980s.

I have specification of a 32x4 bit shift register from RTC  (FDN 106, 
240.00 francs/1  # $50/1) dated 1970.
Other specs are for 256x4 512x2 and 1024x1 but unusable for raster scans. In 
that time (1970) i remember to ask a company to develop a custom 80x8... but 
the cost was too heavy.
Btw, i have specs of TTL used in that design, if anybody need them... (in 
french!)

JMP 




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