Date   : Thu, 05 Mar 1987 00:59:57 GMT
From   : ihnp4!invest!wheaton!cculver@ucbvax.Berkeley.EDU (Calvin Culver)
Subject: Re: Z-80 CP/M Machines

In article <858@crash.CTS.COM> kevinb@crash.CTS.COM (Kevin J. Belles) writes:
>In article <4720@brl-adm.ARPA> 7GMADISO%POMONA.BITNET@wiscvm.wisc.EDU writes:
>>look into a used Tandy Model 4.  It will indeed run CP/M, and a
>>...  For an 'obsolete' machine, the amount of support the
>>Model 4 has has to be seen to be believed!!
>
>   I woudn't suggest a Tandy Model 4 for programming usage. It has the 
>wierdest
>memory banking system I've ever seen, the source code for the BIOS is quite
>difficult to get,...

And several other reasons not to use a Model IV.

I run a Model IV with 2 DSDD 5.25" drives, 390k each, as well as 2 DSDD 8"
1.25 meg each (with a Holmes disk controller), for a total of >3 meg online.
For those who have the hankering for such things, Montezuma Micro provides a
sample BIOS with its documentation (not the actual BIOS, but a stripped-down
version).  I could also install a 256k ramdisk (but with 1228k disks and
access time under 15 ms for a resulting throughput time that would beat the
pants off almost any 8088 machine around, who needs it?), and I
can run at least 4 different operating systems (TRSDOS, which has an
excellent base of Tandy supportware, LDOS, Multidos and CP/M).  True, the
memory banking is somewhat unusual (and, to be fair, has caused some
incompatibility problems with some software--most notably ZCPR3), but is far
from the "weirdest".  In short, the Model IV can be a very good programming
environment.  And it *does* have an impressive amount of support.

                                            --calvin culver--
                                            ...inhp4!invest!wheaton!cculver
                                            Cculver@wheaton.UUCP

      Anyone can make a computer dance with a meg of internal memory
                       Real programmers do it in 8 bits.
                      (Long live CP/M)