Legacy Document
Important: The information in this document is obsolete and should not be used for new development.
Important: The information in this document is obsolete and should not be used for new development.
Controlling Serial Power
The Power Manager provides five procedures that you can use to control power to the serial ports and internal modem.
- Assembly-Language Note
- Although MPW provides assembly-language macros to execute these routines, each of these macros calls the
_SerialPowertrap macro. To call the_SerialPowertrap macro directly, you must first put a routine selector in the D0 register, setting the bits of the selector as follows:
Bit Use 0 Set to 0 to use internal modem; set to 1 to ignore modem. 2 Set to 0 for port B; set to 1 for port A. 7 Set to 0 to switch on power; set to 1 to switch off power. 
Subtopics
- AOn
- AOnIgnoreModem
- BOn
- AOff
- BOff