83Plus:BCALLs:50B3

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Revision as of 02:55, 13 May 2005 by 84plusfreak (Talk | contribs)

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Synopsis

Official Name: Chk_Batt_Low

BCALL Address: 50B3,50B6

Check the batteries.

Inputs

  • None

Outputs

  • Z=1: Batteries are low
  • Z=0: Batteries are good

Registers Destroyed

  • All

Comments

This is not just checking bit 0 of port 2. It puts the calculator into a special mode, creates a delay, polls bit 0 of port 2, and puts the calculator back to normal. BCALLind 50B6 is slightly different from 50B3 because a small delay is done before the routine.

Example

B_CALL Chk_Batt_Low
ret z
B_CALL ChkFindSym
ret c
ld a,b
or a
ret nz
AppOnErr errHand
B_CALL Arc_Unarc
AppOffErr
errHand:
ret