MC68HC908AZ60 Datasheet, PDF (299/480 Pages) Motorola, Inc – HCMOS Microcontroller Unit

Programmable Interrupt Timer (PIT)
Functional Description
INTERNAL
BUS CLOCK
PRESCALER
PSTOP
PRST
16-BIT COUNTER
PRESCALER SELECT
PPS2 PPS1 PPS0
16-BIT COMPARATOR
PMODH:PMODL
Figure 1. PIT Block Diagram
POF
POIE
INTER-
RUPT
LOGIC
Register Name
Bit 7
6
5
4
3
2
1
Bit 0
Read: TOF
0
0
PIT Status and Control Register
(PSC)
Write:
0
POIE PSTOP
PRST
PPS2 PPS1 PPS0
Reset: 0
0
1
0
0
0
0
0
Read: Bit 15
14
13
PIT Counter Register High
(PCNTH)
Write:
Reset: 0
0
0
12
11
10
0
0
0
9
Bit 8
0
0
Read: Bit 7
6
5
4
3
2
1
Bit 0
PIT Counter Register Low
(PCNTL)
Write:
Reset: 0
0
0
0
0
0
0
0
Read:
PIT Counter Modulo Register High
(PMODH)
Write:
Bit 15
14
13
Reset: 1
1
1
12
11
10
1
1
1
9
Bit 8
1
1
Read:
PIT Counter Modulo Register Low
(PMODL)
Write:
Bit 7
6
5
4
3
2
1
Bit 0
Reset: 1
1
1
1
1
1
1
1
=Unimplemented
Figure 2. PIT I/O Register Summary
Table 1. PIT I/O Register Address Summary
Register PSC
Address $004B
PCNTH
$004C
PCNTL PMODH PMODL
$004D $004E $004F
3-tim
MOTOROLA
Programmable Interrupt Timer (PIT)
MC68HC908AZ60 — Rev 2.0
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