MPC555
/
MPC556
QUEUED ANALOG-TO-DIGITAL CONVERTER MODULE-64
MOTOROLA
USER’S MANUAL
Rev. 15 October 2000
13-35
13.12.5 Port Data Direction Register
13.12.6 QADC64 Control Register 0 (QACR0)
Control register zero establishes the QCLK with prescaler parameter fields and de-
fines whether external multiplexing is enabled. All of the implemented control register
fields can be read or written, reserved fields read zero and writes have no effect. They
are typically written once when the software initializes the QADC64, and not changed
afterwards.
DDRQA —
Port QA Data Direction Register
0x30 4808
0x30 4C08
MSB
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
LSB
15
DDQA7
DDQA
6
DDQA
5
DDQA
4
DDQA
3
DDQA
2
DDQA
1
DDQA
0
RESERVED
RESET:
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Table 13-10 DDRQA Bit Descriptions
Bit(s)
Name
Description
0:7
DDQA[7:0]
Bits in this register control the direction of the port QA pin drivers when pins are configured for I/
O. Setting a bit configures the corresponding pin as an output; clearing a bit configures the cor-
responding pin as an input. This register can be read or written at any time.
QACR0 —
QADC64 Control Register 0
0x30 480A
0x30 4C0A
MSB
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
LSB
15
MUX
RESERVED
TRG
RESERVED
PSH
PSA
PSL
RESET:
0
0
0
0
0
0
0
0
1
0
1
1
0
1
1
1
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Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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