# AT91SAM7L128 PIT

## Periodic Interval Timer (PIT) User Interface

### Registers

Register Mapping
Address | Register | Name | Access | Reset
--- | --- | --- | --- | ---
0xFFFFFD40 | Mode Register | PIT_MR | read-write | 0x000FFFFF
0xFFFFFD44 | Status Register | PIT_SR | read-only | 0x00000000
0xFFFFFD48 | Periodic Interval Value Register | PIT_PIVR | read-only | 0x00000000
0xFFFFFD4C | Periodic Interval Image Register | PIT_PIIR | read-only | 0x00000000

### Register Fields

#### PIT Mode Register

Name: PIT_MR

Access: read-write

Address: 0xFFFFFD40

31 | 30 | 29 | 28 | 27 | 26 | 25 | 24
- | - | - | - | - | - | PITIEN | PITEN
23 | 22 | 21 | 20 | 19 | 18 | 17 | 16
- | - | - | - | PIV
15 | 14 | 13 | 12 | 11 | 10 | 9 | 8
PIV
7 | 6 | 5 | 4 | 3 | 2 | 1 | 0
PIV

- PIV: Periodic Interval Value

-

- PITEN: Period Interval Timer Enabled

- 0 = The Periodic Interval Timer is disabled when the PIV value is reached.
- 1 = The Periodic Interval Timer is enabled.

- PITIEN: Periodic Interval Timer Interrupt Enable

- 0 = The bit PITS in PIT_SR has no effect on interrupt.
- 1 = The bit PITS in PIT_SR asserts interrupt.

#### PIT Status Register

Name: PIT_SR

Access: read-only

Address: 0xFFFFFD44

31 | 30 | 29 | 28 | 27 | 26 | 25 | 24
- | - | - | - | - | - | - | -
23 | 22 | 21 | 20 | 19 | 18 | 17 | 16
- | - | - | - | - | - | - | -
15 | 14 | 13 | 12 | 11 | 10 | 9 | 8
- | - | - | - | - | - | - | -
7 | 6 | 5 | 4 | 3 | 2 | 1 | 0
- | - | - | - | - | - | - | PITS

- PITS: Periodic Interval Timer Status

- 0 = The Periodic Interval timer has not reached PIV since the last read of PIT_PIVR.
- 1 = The Periodic Interval timer has reached PIV since the last read of PIT_PIVR.

#### PIT Periodic Interval Value Register

Name: PIT_PIVR

Access: read-only

Address: 0xFFFFFD48

31 | 30 | 29 | 28 | 27 | 26 | 25 | 24
PICNT
23 | 22 | 21 | 20 | 19 | 18 | 17 | 16
PICNT | CPIV
15 | 14 | 13 | 12 | 11 | 10 | 9 | 8
CPIV
7 | 6 | 5 | 4 | 3 | 2 | 1 | 0
CPIV

- CPIV: Current Periodic Interval Value

-

- PICNT: Periodic Interval Counter

-

#### PIT Periodic Interval Image Register

Name: PIT_PIIR

Access: read-only

Address: 0xFFFFFD4C

31 | 30 | 29 | 28 | 27 | 26 | 25 | 24
PICNT
23 | 22 | 21 | 20 | 19 | 18 | 17 | 16
PICNT | CPIV
15 | 14 | 13 | 12 | 11 | 10 | 9 | 8
CPIV
7 | 6 | 5 | 4 | 3 | 2 | 1 | 0
CPIV

- CPIV: Current Periodic Interval Value

-

- PICNT: Periodic Interval Counter

-