80-Bus News

D000 EPROM will go in socket B1 and D400 EPROM in socket B2. Note that ROM ZEAP usually lives at D000 so if you keep ZEAP there you will have to tell Ikon where you wish to put their software. Remember that one of the advantages of a reliable storage system like the Hobbit is that utility programs such as ZEAP, Nasdis, Debug, Pascal and Forth may be used efficiently without using up all your valuable 64 KByte memory page.

The commands and error messages are listed with this article but are much better explained in the Hobbit Booklet. A good description is given of how to use the Hobbit routines in programs. This is so important for educational work where there is a constant need to record results and use large quantities of data. The example program is good but I would have liked a couple more, particularly one inputting data from the tape into the program. It says much for the documentation of the Hobbit and of NASSYS 3 that I have been able to adapt the system to suit our special requirements. Believe me, if I can do it anyone can. I will willingly supply any other school with a copy of my EPROM at cost if they write to me. You will probably prefer to use the information to taylor your own system. I believe that although no source code is provided the Hobbit manual provides all the addresses needed and is a good compromise between perfect documentation and cost.

Finally I must add how using the unit with Blue Label Pascal (now Nascom Pascal) has totally changed my preparation of educational programs. All my Procedures and Functions are recorded onto the Hobbit cassette that contains the Pascal itself. I can get 69 on one side and 58 on the side with the Pascal on. I can find the ones I need for a program quickly, and load them automatically while I drink my coffee. I never have to type the same routine twice, or write one out to keep. I have vowed never to use BASIC again.

But of course the ten and eleven year olds in the school do use BASIC, and the automatic operation of the Hobbit has made things much easier for them too.

A super value product, but I hope I have made clear its limitations without playing down its potential. The manufacturers are most courteous and helpful on the telephone and delivery is very fast and efficient. Our school units were posted two days BEFORE our cheque could possibly have arrived.

	Commands :
B XXXX YYYY	Records a BASIC program, or similar.
C	Change – Used to file a name.
D	Delete – Erase a file.
E	End – rewinds cassette after use.
F	Format a new tape.
K	Kill – deletes all files on a tape.
L XXXX	Loads a file into location XXXX.
M	Mount a new cassette ready to read or load it.
N	Names – List all files on a tape.
R	Read – reads and starts a program.
Sx	Selects one of two drives.
T	Transfers a file from one drive to a second.
X	Return to Nas-Sys.
W XXXX YYYY ZZZZ	Writes a file from location XXXX to location YYYY and if it is a program file will execute it at ZZZZ. Note that it works with BASIC only if BASIC has been cold started.
Z XXXX YYYY	Writes a ZEAP file to tape.

	ERRORS :
A	That file name already exists.
B	Bad file structure.
C	A block won’t read correctly after sixteen tries.
D	Cassette full up.
E	No such file exists on this tape.
G	Cassette has been write-protected.

March–April 1983 · Volume 2 · Issue 2