23 Jul
2008
23 Jul
'08
10:08 p.m.
Chuck,
It has to be done in hardware otherwise why bother. If you want the respect
and awe of the group show us your gravitas and use a spool of fibre optic
cable as the "media" and blink your data in through an LED or LASER diode. A
photo transistor or photo PIN diode at the end will read your data so that
it can be replicated at the beginning of the fibre and start the whole loop
over again. Makes me tingle just thinking about it.
For reference whomever suggested a 555 as a clock source, they crap out at
about 1 MHz. A really good CMOS 555 ( a 7555 ) on a good day may make it to
2 MHz but I wouldn't hold my breathe.
Come on Chuck, show us what your made of .......
Best regards, Steven
I was musing today about the old recirculating stores
(mercury delay
line, magnetostrictive, acoustic, etc.) used for memory on old iron.
Suppose one wanted simulate one in modern components. How would you
do it, if you had, say, a million bits to store?
Would you use a 1x1Mb DRAM and a counter to cycle through the
addresses? Or an 8x128Kb SRAM with an external 8 bit shift register?
Any other thoughts? Access has to be read and write and make the
bitrate about 10MHz.
Cheers,
Chuck