Eprom Programer

[Peter Gargano]

According to my notes, a 2532 is different to
a 2732 as follows:

 24pin  2532     2732      28pin
 --------------------------------
  18     A11     *CE       (20)
  20     *CE   *OE/Vpp     (22)
  21     Vpp     A11       (23)

The 28pin column shows the pin numbers assuming a
28 pin socket is used and the 24 pin device (2532/2732)
is placed so the GND pins share the same pin.

According to an Hitachi HN462532 application note this
is how you program one:

 2532 mode selection  *CE (20)           Vpp (21)
 -------------------------------------------------
 Read                    VIL                5V	
 Standby                 VIH                5V
 Program            VIH->VIL->VIH          25V
 Program Inhibit         VIH               25V

VIL and VIH are of course LOW and HI logic voltage levels.
The SINGLE program pulse is nominally 50 mSec +/- 5 mSec.

I have lots more info on programmers and have designed
my own, using low cost 74LS series TTL logic, for 
connection to a parallel port. Note that the biggest
problem will be writing software for all the different
EPROMs. Perhaps someone knows of a "generic" EPROM
programmer piece of software (with good source code) that 
already knows about different EPROMs? My software's 
"user interface" is still a "work in progress", but it 
does work for 2716s to 27512s.

Another problem to solve is accurate timing of programming 
pulses. A simple solution is to use a 555 timer that the 
software can read (say set at 1 mSec and the software can
count up to 50 for the 2532 described above, and still 
allow "intelligent algorithms" for the "bigger" EPROMs). 
This avoids having to "calibrate" the software for differing 
processor speeds, etc.

If you're (or anyone else) is interested, I could 
convert my schematic from pencil/paper to something
electronic. (please email me direct if you ARE
interested mailto:peter at mail.techedge.com.au this will
avoid unnecessary bandwidth in this discussion group).

Ezekiel Holliday wrote:

> does anyone have the sepcs for programing a 2532. 

-- 
Peter Gargano    peter at mail.techedge.com.au
   http://www.techedge.com.au/teinfo.htm
Ph: +61 2 62515519     Fax: +61 2 6251 6646