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MPC555
/
MPC556
SIGNAL DESCRIPTIONS
MOTOROLA
USER’S MANUAL
Rev. 15 October 2000
2-29
0 = 3-V bus pins full drive (50-pF load)*
1 = 3-V bus pins reduced drive (25-pF load)
* The bus pin drive selectability definition is inverted from the selectability of the pin control in the PDMCR register
(for the TPU, QADC, USIU (SGPIO), QSPI, TouCAN, QSCI, and MIOS pins).
2.4.2 Pad Module Configuration Register (PDMCR)
The slew rate and weak pull-up/pull-down characteristics of some pins are controlled
by bits in the PDMCR. This register resides in the SIU memory map. The contents of
the PDMCR are illustrated below. The PORESET signal resets all the PDMCR bits
asynchronously.
.
.
NOTE:
1. FTPU_PU is only available on mask set K62N and later.
PDMCR
– Pad Module Configuration Register
0x2F C03C
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
SLRC0
SLRC
1
SLRC
2
SLRC
3
Reserved
PRDS
SPRD
S
FTPU
_PU
1
Reserved
HARD RESET:
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
RESERVED
HARD RESET:
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Table 2-3 PDMCR Bit Descriptions
Bit(s)
Name
Description
0
SLRC0
SLRC0 controls the slew rate of the following modules: TPU, QADC, USIU (SGPIO).
0 = Slow slew rate for pins. Controls slew rate pins of 200 ns.
1 = Normal slew rate for pins
1
SLRC1
SLRC1 controls the slew rate of the QSPI and TouCAN modules.
0 = Slow slew rate for pins. Controls slew rate pins of 50 ns.
1 = Normal slew rate for pins
2
SLRC2
SLRC2 controls the slew rate of the QSCI module.
0 = Slow slew rate for pins. Controls slew rate pins of 200 ns.
1 = Normal slew rate for pins
3
SLRC3
SLRC3 controls the slew rate of the MIOS module.
0 = Slow slew rate for pins. Controls slew rate pins of 200 ns.
1 = Normal slew rate for pins
4:5
—
Reserved
6
PRDS
The PRDS bit is used to enable or disable the weak pull-up/pull-down devices in the pads related
to SGPIO and all pads related to IMB modules.
illustrates which pins are affected by
PRDS.
0 = Enable pull-up/pull-down devices
1 = Disable pull-up/pull-down devices
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Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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