![]() |
Routines |
Prev: 28292 | Up: Map | Next: 28334 |
|
||||
28295 | LD E,A | A=N | ||
28296 | ADD A,A | |||
28297 | ADD A,A | |||
28298 | ADD A,E | |||
28299 | ADD A,A | |||
This entry point is used by the routine at 30458 with A=2.
|
||||
28300 | LD D,255 | Prepare DE for subtraction | ||
28302 | NEG | A=-N | ||
28304 | JR 28308 | |||
28306 | LD D,0 | Prepare DE for addition | ||
28308 | LD E,A | Now DE=number of bucks to add (may be negative) | ||
This entry point is used by the routine at 28337 with DE=65535 (-1).
|
||||
28309 | LD HL,(32670) | Collect the current number of bucks from 32670 | ||
28312 | ADD HL,DE | Adjust the number | ||
28313 | INC H | Is the result negative? | ||
28314 | JR NZ,28319 | Jump if not | ||
28316 | LD HL,256 | Set HL up so that the next instruction reduces it to 0 | ||
28319 | DEC H | Restore the value of HL (if it was non-negative), or set it to 0 (if it was negative) | ||
28320 | LD A,H | Set the zero flag if the number of bucks is now 0 | ||
28321 | OR L | |||
28322 | PUSH AF | Save the zero flag temporarily | ||
28323 | LD (32670),HL | Store the new amount at 32670 | ||
28326 | LD DE,20728 | DE=display file address | ||
28329 | CALL 28186 | Print the number of bucks | ||
28332 | POP AF | Restore the zero flag | ||
28333 | RET |
Prev: 28292 | Up: Map | Next: 28334 |