🚀 go-pugleaf

In article <1992Sep2.104405.15299@hemlock.cray.com> kilian@cray.com
(Alan Kilian) writes: 

>The reason we are using the "8" seried 6811 chips with just EEPROM is
>that the 6811 only comes in a plastic case and you can only program
>the EPROM parts ONCE. You cannot erase them like you can with EEPROM

This isn't quite true. 

Motorola makes two packaging styles for the EPROM chips.  The "FS"
package is a ceramic cerquad leaded chip carrier with an erase window
(this part fits into the same socket at the 52-pin PLCC part).  With
this FS package, you can erase the EPROM, but only by exposing it to
ultraviolet light.  Not quite as convenient as the EEPROM
(electrically erasable programmable ROM).

If you get an EPROM part in an FN package (plastic leaded chip
carrier, more commonly known as PLCC), you are buying
"OTPROM"---One-Time Programmable ROM.  Physically, it's the same stuff
as EPROM, but without an erase window, you only get one chance to burn
in your program!

	- Fred
-- 
Fred Martin | fredm@media.mit.edu | (617) 253-7143 | 20 Ames St. Rm. E15-301
Epistemology and Learning Group, MIT Media Lab     | Cambridge, MA 02139 USA