Spring 1979, Issue 2

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NASBUG T4 (Continued)

W Write as in B-BUG. Four times faster than ‘D’.

X Multiple option external mode, which converts Nascom to a full ASCII intelligent terminal. Capable of supporting paper tape with odd or even parity, with or without automatic CR/LF, Teletype as above in half or full duplex, external mainframe timesharing systems through a telephone modem in full or half duplex, odd or even parity, with or without automatic CR/LF, and of course multiple Nascom configurations. This command is possibly the most powerful of all.

Z Directs the Nascom to accept a new command table at the argument supplied by ‘Z’.

? Prints out the current command table in the following format:
A B C D E G I K L M N O Q R S T W X Z ?

Restart vectors (Z80 page 0)

RST 0 (C7) Restart NASBUG T4

RST 8 (CF) ‘Soft restart’ NASBUG T4. As RST 0 but does not clear screen.

RST 16 (D7 xx) Allows relative subroutine calls to be made using displacement (xx). Note that this feature is supported by NASBUG T4 and not by the Z80, and therefore cannot be used in Z80 based systems not using NASBUG T4.

RST 24 (DF xx) Allows a direct call to location 0E00 plus a displacement (xx), the displacements are in 3’s, allowing the user to locate tables, reflective jumps etc. in this area. Note; not supported by Z80 as RST 16.

RST 32 (E7) Breakpoint as in NASBUG T2.

RST 40 (EF) String print as in NASBUG T2.

RST 48 (F7) Direct call to $-CRT

RST 56 (FF) Calls part of KDEL as in NASBUG T2, allowing KDEL to be shortened proportional to the value in A, allows for accurate timing in increments of approx. 50 uS.


The original intention of the INMC software library was to gather together user programs and offer them to members for a minimal photocopying charge – they would be unchecked and untested by the INMC as the originator would presumably have debugged them. However, from the programs that the INMC have so far received we can see that this system will not work – unless you want 8 different versions of Mastermind and 5 Hangmans! We are,

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This is an OCR’d version of the scanned page and likely contains recognition errors.

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