Subject: Re: Hacking the Laser 128EX/2
Path: lobby!newstf02.news.aol.com!audrey03.news.aol.com!not-for-mail
From: supertimer@aol.com (Supertimer)
Newsgroups: comp.sys.apple2
Lines: 37
NNTP-Posting-Host: ladder06.news.aol.com
X-Admin: news@aol.com
Date: 22 Jul 1999 06:38:01 GMT
References: <37912465.2189519@news.remarq.com>
Organization: AOL http://www.aol.com
Message-ID: <19990722023801.01813.00001088@ng-bh1.aol.com>



cranem@athenet.net (Michael Crane) wrote:

>One of the first computers I owned was a Laser 128EX (not the EX/2).
>It sounds like it was much the same as the EX/2 (I think the EX/2 had
>a built in 3.5" drive instead of a 5.25" drive...not sure what else
>might have been different.)  I do recall that it was capable of
>running at 3.6Mhz and 1Mhz, but I am fairly certain it was also able
>to run at 2.xMhz (don't remember the exact number.)

The main difference was 1) the 3.5" drive replaces the 5.25" internal
one (although you could request a 5.25" internal while ordering), 2)
a MIDI port, 3) support of IIGS daisy chain drives so that you could
have more than one drive on the SmartPort and 4) a battery backed
clock and control panel.

Apparently, features 2 through 4 come on an internal card.  If you
look at the motherboard of the EX, look at the socket header at the
upper left hand corner near the expansion slot.  That's where the
feature card plugs into on the EX/2.  According to one of the
designers of the Laser series, plugging the EX/2's feature card into
the EX here will confer most of the EX's features (except the better
UDC chip, which is on the motherboard).

The EX/2 also has several ROM differences.  Because it has more
features, the expansion slot cannot be addressed as Slot 7, only
Slot 5.  Also, while the default power-up speed of the EX is the
"1Mhz" (actually, it is really more like 0.9Mhz rounded up) mode,
the EX/2 boots up in 3.6Mhz mode (it seems the advent of the IIc+
made Laser reconsider which bootup speed was better).  Also, you
could set your own bootup speed of choice, either 3.6, 2.x, or 1Mhz
in the control panel and from then on, the EX/2 would work at that
speed on power up.

One thing that always interested me is the fact that the MIDI output
is going through serial port 2 (addressed as Slot 2) and the serial
port normally supports only up to 19200.  The extra baud rate
needed for MIDI must be provided by the feature card.