Clock Speed Control Register - Texas Instruments MSP50C614 User Manual

Clock Control
The maximum required CPU clock frequency for the C614 is 8 MHz over the
entire V
CPU clock frequencies may be achieved, but these are not qualified over the
complete range of supply voltages in the guaranteed specification.
Figure 2–9. PLL Performance
Oscillator Reference
32 kHz
Resistor
RTO
Trimmed
Selection Made in ClkSpdCtrl
Phase-Locked-Loop circuit
Multiplier Adjusted in ClkSpdCtrl
x 1 ... x 256
2.9.3

Clock Speed Control Register

The ClkSpdCtrl is a 16-bit memory mapped register located at address 0x3D.
The reference oscillator (RTO or CRO) is selected by setting one of the two
control bits located at bits 8 and 9. Setting bit 8 configures the C614 for the RTO
reference option and simultaneously starts that oscillator. Setting bit 9
configures the C614 for the CRO reference option and simultaneously pulses
the crystal, which starts that oscillator.
2-30
range. This rate applies to the speed of the core processor. Higher
DD
crystal
or
CRO
referenced
x4
PLL
Timer Source Option
Selected in IntGenCtrl
1
0
1
TIMER2
0
2
MC
Master Clock : Runs Periphery
131.07 kHz ... 33.554 MHz
2
CPU Clock
Core-Processor Speed
65.536 kHz ... F MAX
(F MAX = 8 MHz)
TIMER2