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Texas Instruments MSP50C6xx User Manual

Page 83

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Interrupt/General Control Register

3-19

Peripheral Functions

The upper four bits in the IntGenCtrl have independent functions. Bit 12 is the
enable bit for the pull-up resistors on port F. Setting this bit applies individual
pull-up resistors to each of the F port pins (see Section 3.1.2, Dedicated Input
Port F
).

Bit 13 is the PDMCD bit for the pulse-density modulation clock. Clearing this
bit yields a PDM clock rate equal to one-half the frequency of the master clock
(i.e., the CPU clock rate). Setting bit 13 yields a PDM rate equal to the rate of
the master clock (see Section 3.2.3, PDM Clock Divider)

Bit 14 is the ARM bit. If the master clock has been suspended during sleep,
then the ARM bit must be set (before the IDLE instruction), in order to allow
a programmable interrupt to wake the MSP50C6xx. Refer to Section 2.11,
Reduced Power Modes, for more information.

Finally, the top-most bit in the IntGenCtrl is the comparator enable bit. Setting
bit 15 enables the comparator and all of its associated functions. Some of the
MSP50C6xx’s conditions, interrupts, and timers behave differently, depending
on whether the comparator is enabled or disabled by this bit. Refer to Section
3.3, Comparator, for a full description.