Inside Macintosh: Devices /

Chapter 6 - Power Manager / Power Manager Reference

Power Manager Routines

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 _SerialPower trap macro. To call the _SerialPower trap 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.

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Subtopics

AOn

AOnIgnoreModem

BOn

AOff

BOff