vsc055xkm-01 Maxim Integrated Products, Inc., vsc055xkm-01 Datasheet - Page 27

• Manufacturer Part Number: vsc055xkm-01
• Description: Enhanced I?c Backplane Controller
• Manufacturer: Maxim Integrated Products, Inc.

VSC055-01
Data Sheet
3.2.12 13h: I/O Port 3 Data Direction (DDP3)
3.2.13 14h: I/O Port 4 Data Direction (DDP4)
The following table shows the bit assignments for the I/O Port 3 Data Direction register. Control of the
individual I/O pins in this register can be overridden by the PBC0, PBC1, PBC2, and PBC3 registers when
port bypass control is required.
The following table shows the bit assignments for the I/O Port 4 Data Direction register.
Control of the individual I/O pins in this register can be overridden by the PBC4, PBC5, PBC6, and PBC7
registers when port bypass control is required.
Register Name:
Address:
Reset Value:
Bit
7:0
Register Name:
Address:
Reset Value:
Bit
7:0
Bit Label
DDP3.7-0
Bit Label
DDP4.7-0
DDP3
13h
1111_1111b
DDP4
14h
1111_1111b
Access Description
R/W
Access
R/W
Data Direction
These bits determine the direction of the data flow through the I/O pin.
To enable the respective I/O pin as an input, set the appropriate bit.
To enable the respective I/O pin as an output, reset the appropriate bit.
Each I/O pin can be individually configured as a true bidirectional function. To
implement an open-drain or open-source function, set or reset the appropriate
data bit using the data direction bit as the programmed data value.
After a reset or power on, these bits are set to a binary 1, enabling the I/O as an
input with weak pull-up.
Description
Data Direction
These bits determine the direction of the data flow through the I/O pin.
To enable the respective I/O pin as an input, set the appropriate bit.
To enable the respective I/O pin as an output, reset the appropriate bit.
Each I/O pin can be individually configured as a true bidirectional function. To
implement an open-drain or open-source function, set or reset the appropriate
data bit using the data direction bit as the programmed data value.
After a reset or power on, these bits are set to a binary 1, enabling the I/O as an
input with weak pull-up.
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January 2008
Revision 4.1