Words

on Jupiter Ace

This is a listing of Forth words. These words will fit on any Jupiter

Ace regardless of memory and are intended to provide missing or helpful features for the competent

programmer. Simply type them in as they are printed and they will be ready for use.

This requires two numbers on the stack, on top a delimiter and second from top an address. What it does is give the user a chance to type in a string and then it will put the first character to the specified address, the second to the address + 1 and so on. This is handy as it allows several messages to be typed in and stored in memory leaving the Pad free for more immediate things.

: EXPECT
  QUERY WORD C@ 0
  DO
   9986 I+ C@ OVER
   I+ C!
  LOOP
  DROP
;

This simply tells the user how many spare bytes are left for Forth programming.

: MEM
  15384 @ HERE - CR
  ." Bytes left."
  CR
;

This needs two numbers on the stack, a line number second from top and on top a column number. It will leave on top of the stack the character code of the character at those screen coordinates and also set the print position to those coordinates as well.

: SCREENS
  AT 15388 @ C@
;

This will tell the user the present number base in decimal, eg, if the computer is working in Hex ?base will display Base 16. It does not alter the number Base.

: ?BASE
  BASE C@ DUP DECIMAL
  CR ." Base" . CR
  BASE C!
;

This word will reset various system variables, they are;
Base set to 10 (ie, decimal). Visible mode restored. Slow mode restored. Both stacks are cleared and screen is cleared.

: NORMAL
  CLS DECIMAL VIS
  SLOW QUIT
;

Words
by A Cranston