Lucas Logic apparently have lost their commitment to Nascom
Microcomputers and products. Their relationship with Dealers is appalling.
The sooner Nascom is bought by a decent company the better. In my
opinion in their hands Nascom is dead.
Yours in extreme anger and disappointment,
Dr D Plews, MB ChB, Keighley, W Yorks
Rory a Sadist?
Whilst reading Rory O’Farrell’s article
I got the
impression that he is some sort of sadist. The time taken to load a file into
a disassembler, save it into 4K blocks as a hex file, then finally to transfer
the file, must be a least 10 minutes per block.
For some time now, I have been working on a quick and cheap data transfer
program for the home enthusiast. The transmitting of data is done via a BASIC
program which reads any file type and transmits via the serial port. For
reasons mentioned in Rory O’Farrell’s article, the program cannot transmit
pure binary object code, it is therefore necessary to convert the file to some
form that may be recognised by PIP and not to send it Control Zs. The file is
received on the second machine via the RDR: into a file. A small BASIC
program is then required to convert the program back into its binary form.
Finally, a little tip for NASCOM CP/M users using the
most people boot-up CP/M they type AVCTXT straight away to give an 80 column
screen, or modify the BIOS via the config program to execute a file AUTO.SUB.
You then create the file AUTO.SUB and enter the command AVCTXT.
Have you ever wondered why it takes 15-20 seconds to execute AVCTXT after
boot-up? The reason is simple, when Auto load is specified, it sets a jump in
the BIOS, the address jumped to is to load SUBMIT.COM, it is then the job of
SUBMIT.COM to load AVCTXT and execute it, therefore, taking time loading two
files to achieve one goal.
Pondering on this, I decided to delve into MOVCPM. I found the bytes
which loaded SUBMIT.COM and changed these to AVCTXT and resaved MOVCPM. CP/M
now boots-up AND executes AVCTXT in less than 5 seconds. The trick is:
– D 0A00
Notice that locations 0A08 – 0A17 contain SUBMIT AUTO.
Change these locations to the following:–
0A07 – This is the length of the command to be executed
0A08 41 A
0A09 56 V
0A0A 43 C
0A0B 54 T
0A0C 58 X
0A0D 54 T
SAVE 41 MOVCPM.COM
MOVE 55 *
SOURCE (press enter)
Yours faithfully, P.A. Dutton, Northfield, Birmingham.