Programmable Interrupt Timers (PIT0–PIT1)
Freescale Semiconductor
22-2
MCF52235 ColdFire® Integrated Microcontroller Reference Manual, Rev. 6
NOTE
The low-power interrupt control register (LPICR) in the system control
module specifies the interrupt level at or above which the device can be
brought out of a low-power mode.
In wait mode, the PIT module continues to operate as in run mode and can be configured to exit the
low-power mode by generating an interrupt request. In doze mode with the PCSR
n
[DOZE] bit set, PIT
module operation stops. In doze mode with the PCSR
n
[DOZE] bit cleared, doze mode does not affect PIT
operation. When doze mode is exited, PIT continues operating in the state it was in prior to doze mode. In
stop mode, the internal bus clock is absent and PIT module operation stops.
In debug mode with the PCSR
n
[DBG] bit set, PIT module operation stops. In debug mode with the
PCSR
n
[DBG] bit cleared, debug mode does not affect PIT operation. When debug mode is exited, the PIT
continues to operate in its pre-debug mode state, but any updates made in debug mode remain.
22.2
Memory Map/Register Definition
This section contains a memory map (see
) and describes the register structure for PIT0–PIT1.
Table 22-1. PIT Module Operation in Low-power Modes
Low-power Mode
PIT Operation
Mode Exit
Wait
Normal
N/A
Doze
Normal if PCSRn[DOZE] cleared,
stopped otherwise
Any interrupt at or above level in LPICR, exit doze
mode if PCSRn[DOZE] is set. Otherwise
interrupt assertion has no effect.
Stop
Stopped
No
Debug
Normal if PCSRn[DBG] cleared,
stopped otherwise
No. Any interrupt is serviced upon normal exit
from debug mode
Table 22-2. Programmable Interrupt Timer Modules Memory Map
IPSBAR Offset
Register
Width
(bits)
Access
1
1
Accesses to reserved address locations have no effect and result in a cycle termination transfer error.
Reset Value
Section/Page
PIT 0
PIT 1
Supervisor Access Only Registers
2
0x15_0000
0x16_0000
PIT Control and Status Register (PCSRn)
16
R/W
0x0000
0x15_0002
0x16_0002
PIT Modulus Register (PMRn)
16
R/W
0xFFFF
User/Supervisor Access Registers
0x15_0004
0x16_0004
PIT Count Register (PCNTRn)
16
R
0xFFFF
Because
of
an
order
from
the
United
States
International
Trade
Commission,
BGA-packaged
product
lines
and
part
numbers
indicated
here
currently
are
not
available
from
Freescale
for
import
or
sale
in
the
United
States
prior
to
September
2010:MCF52234CVM60,
MCF52235CVM60
