home *** CD-ROM | disk | FTP | other *** search
- Newsgroups: comp.dcom.modems
- Path: sparky!uunet!munnari.oz.au!spool.mu.edu!yale.edu!qt.cs.utexas.edu!cs.utexas.edu!swrinde!zaphod.mps.ohio-state.edu!wupost!micro-heart-of-gold.mit.edu!uw-beaver!cs.ubc.ca!newsserver.sfu.ca!sfu.ca!mckeeveb
- From: mckeeveb@monashee.sfu.ca (Gumby - The unknown user)
- Subject: Re: Upgrading a ZyXEL 1496E to an E+
- Message-ID: <mckeeveb.726729008@sfu.ca>
- Sender: news@sfu.ca
- Organization: Simon Fraser University, Burnaby, B.C., Canada
- References: <93Jan08.021101.27410@acs.ucalgary.ca> <1inih0INNqsh@mudos.ann-arbor.mi.us> <mckeeveb.726656955@sfu.ca> <1iqin8INN4k2@mudos.ann-arbor.mi.us>
- Date: Mon, 11 Jan 1993 05:10:08 GMT
- Lines: 55
-
- mju@mudos.ann-arbor.mi.us (Marc Unangst) writes:
-
- >Then I stand corrected. I'm now sorry that I didn't get a chance to
- >take a look at the E+ we had in a week ago; we'll probably never sell
- >one (too much extra cost for too little extra features), and it would
- >have been nice to compare them.
-
- The latest round of boards are basically E+ machines with a few minor
- changes:
-
- 1) a 12 MHz CPU rather than 16MHz running at 20..
- 2) Custom labelled DSP chips with internal RAM to avoid the daughter board.
-
- >For reference: I have a ZyXEL U-1496E, s/n S2B0230110, mainboard s/n
- >2A00227492. The mainboard appears to be rev. B1. The piggyback DSP
- >RAM board is the 1992 model, rev. 1. There is a jumper wire soldered
- >between the far two pins on jumper J3, and no jumper wire on J4.
-
- That's the larger RAM board...
-
- >Now, are you telling me that simply by putting in a new DSP RAM board,
- >changing that jumper wire, and loading E+ EPROMs, I could have an E+?
- >If this is true, then the upgrade would definitely be worthwhile. If,
- >on the other hand, we're still talking about replacing the 68000 with
- >a faster model or other complex modifications, I'll stand by my
- >position that an E->E+ upgrade is not practical.
-
- There may also be a checksum/serial number/model number programmed into
- the EEPROM where the profiles are stored. (this is a 512 byte EEPROM of
- which there are 4 profiles of 56 bytes each and some phone numbers and
- passwords... lots of spare room)
-
- >>On all the units made after the E+ was released, there is a jumper on the
- >>main board to select processor speed. There really is no difference.
-
- >I'm assuming that this is the soldered jumper under the DSP RAM board
- >and behind the DTR LED, not some other jumper that's using a jumper
- >block.
-
- Actually, I think the speed is handled by two jumpers (each of which
- has 'CK' in their labelling)
-
- >Interestingly enough, there are also a few empty solder pads to the
- >left of the 68000 chip. There are two marked JP2, two marked C97, two
- >marked L3, and a 14-pin DIP marked U41. To the right of the 68000
- >there is another empty capacitor, C87. Does anyone know if these
- >board positions are used in the E+?
-
- Not sure... I'll get back to you on that.
-
- --
- Rob McKeever VE7ICJ rmckeeve@sfu.ca mckeeveb@sfu.ca 604-291-0457
- "Do you know what standards are? They're career paths for people who don't
- want to work!" - John Parkinson, Ernst & Young at the BCDMA Conference '92
- -*- Standard Disclaimers should be adequate -*-
-