AT83C5122_08 ATMEL [ATMEL Corporation], AT83C5122_08 Datasheet - Page 51

• Manufacturer Part Number: AT83C5122_08
• Description: C51 Microcontroller with USB and Smart Card Reader Interfaces
• Manufacturer: ATMEL [ATMEL Corporation]

I/O Port Definition
Ports vs Packages
Port 0
4202F–SCR–07/2008
Table 30. I/O Number vs Packages
Port 0 has the following functions:
Port 0 has the following configurations:
VQFP64
VQFP32
PLCC28
QFN64
QFN32
–
–
–
–
–
Default function: Port 0 is an 8-bit I/O port.
Alternate function: Port 0 is also the multiplexed low-order address and data
bus during accesses to external Program and Data Memory. In this
application, it uses strong internal pull-ups when emitting 1’s and it can drive
CMOS inputs without external pull-ups.
Default configuration: open drain bi-directional I/O port. Port 0 pins that have
1’s written to them float, and in this state they can be used as high-
impedance inputs.
Configuration 2: Low speed output, “KB_OUT”
Configuration 3: Push-pull output
P0
8
-
-
P1
8
8
6
AT83R5122, AT8xC5122/23
P2
8
-
-
P3
8
8
6
P4
6
-
-
P5
8
1
1
Total
46
17
13
51