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The address of this routine is derived from an offset found in the command class table.
This subroutine allows for the current temporary colours to be made permanent. As command class 7 it is in effect the command routine for the six colour item commands.
CLASS_07 07318 BIT 7,(IY+1) The syntax/run flag (bit 7 of FLAGS) is read.
07322 RES 0,(IY+2) Signal 'main screen' (reset bit 0 of TV-FLAG).
07326 CALL NZ,TEMPS Only during a 'run' call TEMPS to ensure the temporary colours are the main screen colours.
07329 POP AF Drop the return address SCAN_LOOP.
07330 LD A,(23668) Fetch the low byte of T-ADDR and subtract 19 to give the range 217 to 222 which are the token codes for INK to OVER.
07333 SUB 19
07335 CALL CO_TEMP_4 Change the temporary colours as directed by the BASIC statement.
07338 CALL CHECK_END Move on to the next statement if checking syntax.
07341 LD HL,(23695) Now the temporary colour values (ATTR-T and MASK-T) are made permanent (ATTR-P and MASK-P).
07344 LD (23693),HL
07347 LD HL,23697 This is P-FLAG, and that too has to be considered.
07350 LD A,(HL)
The following instructions cleverly copy the even bits of the supplied byte to the odd bits, in effect making the permanent bits the same as the temporary ones.
07351 RLCA Move the mask leftwards.
07352 XOR (HL) Impress onto the mask only the even bits of the other byte.
07353 AND %10101010
07355 XOR (HL)
07356 LD (HL),A Restore the result.
07357 RET
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