Routines
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07642: THE 'NEXT-LOOP' SUBROUTINE
Used by the routines at FOR and NEXT.
This subroutine is used to determine whether the LIMIT (l) has been exceeded by the present VALUE (v). Note has to be taken of the sign of the STEP (s).
The subroutine returns the carry flag set if the LIMIT is exceeded.
NEXT_LOOP 07642 RST 40 -
07643 DEFB 225 get_mem_1: l
07644 DEFB 224 get_mem_0: l, v
07645 DEFB 226 get_mem_2: l, v, s
07646 DEFB 54 less_0: l, v,( 1/0)
07647 DEFB 0 jump_true to NEXT_1: l, v, (1/0)
07648 DEFB 2
07649 DEFB 1 exchange: v, l
NEXT_1 07650 DEFB 3 subtract: v-l or l-v
07651 DEFB 55 greater_0: (1/0)
07652 DEFB 0 jump_true to NEXT_2: (1/0)
07653 DEFB 4
07654 DEFB 56 end_calc: -
07655 AND A Clear the carry flag and return - loop is possible.
07656 RET
However if the loop is impossible the carry flag has to be set.
NEXT_2 07657 DEFB 56 end_calc: -
07658 SCF Set the carry flag and return.
07659 RET
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