EXTRA NOTES FOR PIC DATA LOGGER - 30JUN99 - amended 01NOV99

The following files are supplied on PIC DISK 2 (from EPE HQ) and from
the EPE FTP site:

DATLOG02.ASM  - PIC source code (written in TASM) V1.2
DATLOG02.OBJ  - PIC object code V1.2
DATLOG02.BAS  - QBasic/QuickBASIC data transfer program V1.1
DATLOG01.COM  - Machine code for use with DATLOG02.BAS *
DATLOG01.J    - Machine code source file (written in A86) *
DATLOG02.COM  - Alternative machine code for use with DATLOG02.BAS *
DATLOG02.J    - Alternative machine code source file (written in A86) *
(* - see below)

Versions V1.1 (BAS) and V1.2 (PIC) have had some changes made from the orig.

Copy the .BAS, .COM and .J files into the same directory that holds your
QBasic/QuickBASIC programs.

Copy the .ASM and .OBJ files into your PIC directory.

Now create the directory (envlope) "C:\PICLOG" before you run the BASIC
program, e.g. from DOS mode type:

C:
CD\
MD PICLOG

Machine code file "DATLOG01.COM" is that originally used by the author. It
has a latent problem for other users in that if data is not received from
the Data Logger once the machine code routine has been entered, the software
gets "hung-up". The only way out of this situation if data reception
continues to fail is to use ALT-CTRL-DEL to reset the computer.

Machine code file "DATLOG02.COM", however, has an additional routine in
which the keyboard is scanned for the pressing of letter "Q" (upper or
lower case). If "Q" is detected the machine code is aborted and the
BASIC screen confirms that this has been done. However, although this
version has been used successfully on three of the author's computers, on
a fourth it failed to respond to the serial data being sent, even though it
responded to the pressing of "Q". The reason is not known (but the computer
in question was "tailor-made" for EPE, whereas the others are normal
"commercial" products - 2 Dells and a Compaq).

The choice of which file is accessed from the BASIC program is given near
the start of the BASIC listing. Try them both and choose which ever one
works best for you - delete the REM character (') from one, and place it
in front of the other line, e.g., the following activates DATLOG01.COM:

file$ = "DATLOG01.COM"
'file$ = "DATLOG02.COM"

whereas this activates DATLOG02.COM:

'file$ = "DATLOG01.COM"
file$ = "DATLOG02.COM"

Additionally be aware that with both versions, the first data byte received
from Data Logger Channel 1 is occasionally corrupted, resulting in the rest
of that channel's data being corrupted, and occasionally that of the other
channels as well. The reason is not known. The situation reveals itself
on the transfer screen by data values for Channel 1 having five digits
instead of the usual four or less, accompanied by a loss of correct screen
format display. In this situation it may be necessary to press "Q" to quit
the transfer, or to press the Logger's SEND (S2) switch again once it has
completed sending the data. The transfer routine should then be run again
from the beginning. It is a rare situation, but seems to occur only when
the program is freshly loaded when the COM port has not been used since
the computer was first switched on.

If anyone can throw light on why these problems occur, and offer a solution,
please tell John Becker at EPE.

Finally, just as a reminder, the BASIC program must be set to suit the COM 
port being used by the computer, e.g.:

for COM1 set comport% = 0
for COM2 set comport% = 1

The "comport%" variable line is a few lines lower in the program than the
"file$ = " lines just discussed.

John Becker 30JUN99

