Nascom News­let­ter

Assembler.

Symbol tables can be created, sorted alphabetically, saved and, more importantly, invoked from a pseudo op as an external set of labels on disc in which case there is no check for re-definition and that I do lament.

LIST – has many forms (source listing is done from the Editor by CTRL X).

LINES & MARGIN – control the listing position and length on paper (and in fact).

DIR – directories of your disc can be seen easily but only on one disc.

DISC – allows you to designate a working disc if you want a different one so you don’t have to specify which disc all the time. This is more useful than a limitations.

There are two modes of assembly, one (1) for single origin and, my preference, mode 0 for multi-origin assemblies. The latter creates file which can dump the code in many absolute locations when called via the assembler.

One more lament – I haven’t been able to execute files like DEBUG direct from assembler. Perhaps I shouldn’t try but I would like to have succeeded.

Pseudo Ops.

PUSH’S or POP’s – can be strung on one line – neat.

NOP 4 – some mnemonics can be repeated by following them with a number. Very mice.

Binary, hex, decimal plus any radix up to 16 can be handled using Q. Octal freaks will like this if there are still any around.

ENDP – listings can be thrown to a new page at will.

PAUSE – nice op to stop assembly. Gives you time to think before ploughing on.

COND/​ENDC – gives conditional assembly.

QUERY – requests a value during assembly. Can be used with above to form fancy conditional assemblies.

PRINT – displays during assembly – useful.

FOR/​NEXT – creates repetative code with few labels in each iteration.

MACR/​RPT – repeats code n+i times – not as useful as above

INSERT – allows a side file to be inserted from disc during assembly. A good working assembly could be accessed with this.

DEFL – all the old faithfulls are there plus this one which allows a label to be redefined.

ADDR – reverses the byte order in a word as per 6800. Cross assembly is possible by getting other versions of this assembler.

EXEC – allows a machine code routine to be executed. Strange one this but I could make good use of it given time.

LRRC, etc – logical shifts and inverts can be performed on labels – has possibilities.

NAME – puts the name on every page – date and time if you need and I do minutes as well!

OPCD – this in a macro but you define the code in hex. The