[net.micro.trs-80] Model II/12 CP/M

toma@tekchips.UUCP (Tom Almy) (09/24/84)

	I am/was interested in purchasing CP/M+ (the R.S. product) for
a model II.  None of the stores stock it and the "help" line from Fort
Worth is of no assistance with my questions.  Could anyone out there
answer any of the following:

1. Does the bios support terminal emulation commands for "insert line"
   and "delete line" as well as the (to be expected) "cursor position"
   "delete to end of line" and "delete to end of screen".  Does it 
   emulate any real terminal; if so, which one.

2. What is the disk capacity?  Can double sided drives be used?

3. Are the I/O vector words implemented (in other words, does the DEVICE
   command work?).  Is the clock implemented?

4. What is the TPA value?  I assume that only the non-banked CP/M is
   available, since the banked version would not work with the Model II's
   bank switching scheme (or am I wrong).


	I would also like to know the answers to questions 1 and 2
for Pickles and Trout V2.2 CP/M.  I use FMG, and want to run an application
program which requires insert line and delete line.

Tom Almy (decvax|ucbvax| many others)!tektronix!tekchips!toma

res@ihuxn.UUCP (Rich Strebendt) (09/28/84)

In reply to:

| 	I am/was interested in purchasing CP/M+ (the R.S. product) for
| a model II.  None of the stores stock it and the "help" line from Fort
| Worth is of no assistance with my questions.  Could anyone out there
| answer any of the following:

I also recently got CP/M for my Model II, but I gave up on the Radio
Shack version in disgust and bought Aton CP/M 2.25 instead.  I have
been very well pleased with it.  While it is a 2.2 version of CP/M, it
incorporates a number of 3.0 features as well.  Also, I have been
pleased with the service I have gotten in answer to my questions.  
So, I will try to answer your questions FOR THE ATON VERSION instead.

| 1. Does the bios support terminal emulation commands for "insert line"
|    and "delete line" as well as the (to be expected) "cursor position"
|    "delete to end of line" and "delete to end of screen".  Does it 
|    emulate any real terminal; if so, which one.

The Aton CP/M supports these functions.  I emulates both a SOROC and
the VT-100 terminals, selected during system reconfiguration (which can
be done any time at level1 <discussed below> and takes effect after a 
warm boot).  

| 2. What is the disk capacity?  Can double sided drives be used?

Aton has 600K per SSDD disk.  Double sided drives are supported.  Since
I do not have any DSDD disks I cannot quote capacity figures off of the
top of my head.  As a side light, the formatter can format disks in
several formats:

	Standard CP/M SSSD format (used for interchange of programs
		with other kinds of machines running CP/M)
	Aton SSDD format (the format I use except when exchanging 
		software)
	Aton DSDD format (Alas, I have no double sided drives)
	Pickels and Trout SSDD format (not recommended by Aton for 
		performance reasons, but provided for ease of
		interchange with machines running P&T)
	Radio Shack TRSDOS format (not too useful to me, but might 
		be to others since the Aton formatter is lots faster
		than the TRS one).

| 3. Are the I/O vector words implemented (in other words, does the DEVICE
|    command work?).  Is the clock implemented?

Sorry, am not familiar with the DEVICE command (I am still in the
novice class).  However, as nearly as I can tell, this is a very
complete implementation of CP/M, so if that is a standard feature of
CP/M I am fairly confident that it is implemented in this version.
Aton CP/M maintains a clock display on the status line which can be set
by command or by a device which plugs into one of the RS-232 ports, if
that is what you meant by the second part of this question.

| 4. What is the TPA value?  I assume that only the non-banked CP/M is
|    available, since the banked version would not work with the Model II's
|    bank switching scheme (or am I wrong).

Aton's CP/M does not add bank switched memory transparently to the TPA.
However, if you have additional memory and are programming an
application in assembler, you can do the bank switching without
interference, or you can tell the CP/M OS to go find all of the extra
memory it can and use some of it for disk track caches.  The latter is
invoked through the command "LEVEL2" and yields five track buffers in
the 64K of extra memory I have, plus some that I can use by bank
switching if I want to.  In level2 the TPA is somewhat larger than in
level1 since I/O buffers are moved to the extra memory.  The effect of
having disk track caches is to give the Model II with floppy drives a
level of performance comparable to a system with hard disks for I/O
intensive work (such as compilation).


If you can find them, I strongly recommend a pair of articles that
appeared in the two/sixteen magazine in the last couple of years.
These articles compared the versions of CP/M for the Model II and 16
computers and did so in quite a bit of detail.  The author was not as
familiar with Aton CP/M as he was with P&T CP/M, so there is a small
amount of bias there, but the articles are otherwise very good.  This
magazine is now named "Advanced Computing" but is still aimed at the
users of Radio Shack Models II, 12, 16, 100, ... serious computers (as
opposed to the Model I, III, 4, ... toys).

If you have further questions about Aton CP/M I would be quite willing
to try to answer them for you if you would send them to me by mail to
the electronic address below.  In the event that you cannot get through
by electronic means, I have included my surface mail address as well.

					Rich Strebendt
					...!ihnp4!ihuxn!res

					Room 2F-426
					AT&T Bell Laboratories
					1100 E. Naperville Rd.
					Naperville, IL  60566