8.8.5
LDT/PIT Status & Control Register
7
6
5
4
3
2
1
0
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RFU
RFU
CLOCK
INTERRUPT
MODE
MODE
MODE
RUN
SELECT
FLAG
2
1
0
Bit 0: LDT/PIT Run (Read/Write)
This bit controls whether the LDT/PIT runs or is stopped.
0 = stop (default)
1 = run
Bits 3 - 1: LDT/PIT Mode (Read/Write)
These bits set the mode of the timer as follows:
000 = LDT
001 = PIT 100Hz
010 = PIT 200Hz
011 = PIT 500Hz
100 = PIT 1,000Hz
101 = PIT 2,000Hz
110 = PIT 5,000Hz
111 = PIT 10,000Hz
All frequencies are with a 1MHz clock source selected via bits 6 and 5.
Bit 4: LDT/PIT Interrupt Flag (Read/Clear)
This bit is set if the LDT RUN bit is set AND either the LDT rolls over or the PIT interval expires.
This bit can be cleared by writing to the register with a zero in its bit position. This should be
done in the LDT/PIT interrupt service routine.
0 = LDT/PIT interrupt has not occurred
1 = LDT/PIT interrupt has occurred
Bits 5: Clock Source Select (Read/Write)
These bits select the clock source for the LDT/PIT as follows:
0 = HFCLK/4
1 = LFCLK
Bit 6-7: Reserved
8-16
VP 110/01x
Additional Local I/O Functions
Содержание VP 110/01 Series
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