Power Management
MCF52235 ColdFire® Integrated Microcontroller Reference Manual, Rev. 6
Freescale Semiconductor
9-9
9.3
IPS Bus Timeout Monitor
The IPS controller implements a bus timeout monitor to ensure that every IPS bus cycle is properly
terminated within a programmed period of time. The monitor continually checks for termination of each
IPS bus cycle and completes the cycle if there is no response when the programmed monitor cycle count
is reached. The error termination is propagated onto the system bus and eventually back to the ColdFire
Core.
IPSBAR
Offset:
0x11_0007 (LPCR)
Access: read/write
7
6
5
4
3
2
1
0
R
LPMD
0
STPMD
0
LVDSE
0
W
Reset:
0
0
0
0
0
0
0
0
Figure 9-6. Low-Power Control Register (LPCR)
Table 9-8. LPCR Field Descriptions
Field
Description
7–6
LPMD
Low-power mode select. Used to select the low-power mode the chip enters after the ColdFire CPU executes the
STOP instruction. These bits must be written prior to instruction execution for them to take effect. The LPMD[1:0]
bits are readable and writable in all modes. The four different power modes that can be configured with the LPMD
bit field are illustrated below:
Note: If LPCR[LPMD] is cleared, then the device stops executing code upon issue of a STOP instruction.
However, no clocks is disabled.
5
Reserved, should be cleared.
4–3
STPMD
PLL/CLKOUT stop mode. Controls PLL and CLKOUT operation in stop mode as shown in
2
Reserved, should be cleared.
1
LVDSE
LDV standby enable. Controls whether the PMM enters VREG Standby Mode (LVD disabled) or VREG
Pseudo-Standby (LVD enabled) mode when the PMM receives a power down request. This bit has no effect if the
RCR[LVDE] bit is a logic 0.
1 VREG Pseudo-Standby mode (LVD enabled on power down request).
0 VREG Standby mode (LVD disabled on power down request).
0
Reserved, should be cleared.
LPMD[1:0]
Mode
11
STOP
10
WAIT
01
DOZE
00
RUN
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
