Winter 1978, Issue 1

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Zeap is an excellent in-store assembler, produced by Paul Chapman and Geoffrey Roughton. Its main features are

  • users only 2.75K memory (how they did that we don’t know)
  • uses standard Z80 mnemonics
  • includes powerful screen editor
  • program storage on cassette tape

Cassettes are available at £32.00. A brochure is enclosed with this newsletter.

Tiny Basic

Nascom Tiny Basic is a version of Palo Alto Tiny Basic with some useful extensions. In particular it allows storage and retrieval of programs from cassette and includes a machine code subroutine call facility which allows you to extend it to do things like address vdu RAM directly, control PIO’s etc.

This makes it ideal for games and control applications requiring no floating point. It is being distributed on two EPROMs and will be released in December with the memory boards. We’ve been using Tiny Basic on a prototype extended Nascom for sometime now and it is amazing how quickly you can get quite complicated programs working.

Driving Printers

A Centronics printer can easily be interfaced to the PIO by making up a cable as follows:

Nascom Centronics
Port A
Data 0 (1) ______________ (2) Data
Data 1 (2) ______________ (3) Data
Data 2 (3) ______________ (4) Data
Data 3 (4) ______________ (5) Dat
Data 4 (5) ______________ (6) Data
Data 5 (6) ______________ (7) Data
Data 8 (7) ______________ (8) Data
Data 7 (8) ______________ (1) Strobe
GND (9) ______________ (14) GND

Port B
Data 7 (8) ______________ (11) Busy
GND (9) ______________ GND
BSTB (11) ___|

A software routine to drive the printer is listed below. We are reproducing it here since it may also be of interest to those with other types of printers or driving other devices via the P.I.O.

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