eproms

[Mike Rolica]

Extremely!!  Iguess I can try using a 256 or 512 prom burn it and try it?
Mike Rolica
EXT. 260
 :-)


	-----Original Message-----
	From:	Marteney, Steven J. [SMTP:smarteney at xlvision.com]
	Sent:	Wednesday, November 10, 1999 2:47 PM
	To:	gmecm at efi332.eng.ohio-state.edu
	Subject:	RE: eproms

	If the address range is only 12K, why would a 27C128 be used?  The
HC11's
	I've worked with have a multiplexed 8-bit data bus with a 16-bit
address
	bus.  Maximum address space then is 64KB.  I also know the largest
register
	in the HC11 (ones I've worked with) is 16-bit (PC, Index X and Y,
others) so
	it's internal address capabilities should be limited to 64kB.
However, I
	don't know how other variants work.  There are some glue chips
available
	from Motorola that do certain things (HC24 comes to mind) but don't
of any
	that expand the address space.  Now I'm wondering where the 27c128
came
	from?

	As for Mike's timing questions, I can not address ABSOLUTE timing
'cause I
	don't know.  What I would do is try to get datasheets on both parts
and
	compare the timing parameters (setup and hold times, clock to output
delays,
	read cycle timing, write cycle timing) and just get a warm fuzzy
that the
	two are similar enough to work.

	Is this helpful?
	Steve

	-----Original Message-----
	From: Akselrud, Boris [mailto:AkselruB at moodys.com]
	Sent: Wednesday, November 10, 1999 1:40 PM
	To: 'gmecm at efi332.eng.ohio-state.edu'
	Cc: 'mrolica at meridian-mag.com'
	Subject: RE: eproms


	1. I don't think you can use 27c512 in ECM designed to rad 27c128,
because
	address buss will only address 12K
	2. Blank eeproms can be ordered from www.digikey.com
	3. If you use eeprom, make sure that it's timing is as fast or
faster then
	EPROM's

	-----Original Message-----
	From: Mike Rolica [mailto:mrolica at meridian-mag.com]
	Sent: Wednesday, November 10, 1999 1:02 PM
	To: Gmecm (E-mail)
	Subject: eproms


	OK, so I have a 87 165 ecm with a 27c128 eprom.  Now a couple of
questions.
	Can I huse a 27c512 eprom cause it has extra room?  What would I
have to do
	to use this one and/ or why can't I?  Second I have asked this
question
	before... but can I use a eeprom instead (so I don't have to erase
it uv all
	the time) ?
	Lastly  where would I find some blank eproms ?
	Mike Rolica
	EXT. 260
	 :-)