| Routines

13561: THE 'GREATER THAN ZERO' OPERATION (offset 55)

Used by the routine at compare. The address of this routine is found in the table of addresses. It is called via the calculator literal 55 by the routines at NEXT_LOOP, PRINT_FP, ln, get_argt and to_power. This subroutine returns a 'last value' of one if the present 'last value' is greater than zero and zero otherwise. It is also used by other subroutines to 'jump on plus'.
Input
HL | Address of the first byte of the number
greater_0 | 13561 | CALL TEST_ZERO | Is the 'last-value' zero?
| 13564 | RET C | If so, return.
| 13565 | LD A,255 | Jump forward to less_0 but signal the opposite action is needed.
| 13567 | JR SIGN_TO_C