ST72T331 STMICROELECTRONICS [STMicroelectronics], ST72T331 Datasheet - Page 30

• Manufacturer Part Number: ST72T331
• Description: 8-BIT MCU WITH 8 TO 16K OTP/EPROM, 256 EEPROM, 384 TO 512 BYTES RAM, ADC, WDG, SCI, SPI AND 2 TIMERS
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

ST72E331 ST72T331
I/O PORTS (Cont’d)
Table 11. Port Configuration
Notes:
1. ST72T331N only
2. For OTP/EPROM version, when OR=0: floating & when OR=1: reserved
3. For OTP/EPROM version, when OR=0: open-drain, high sink capability & when OR=1: reserved
* Reset state (The bits corresponding to unavailable pins are forced to 1 by hardware, this affects the reset status value).
Warning: All bits of the DDR register which correspond to unconnected I/Os must be left at their reset value. They must
not be modified by the user otherwise a spurious interrupt may be generated.
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Port A
Port B
Port C
Port D
Port E
Port F
Port
PF4, PF6, PF7
PD6:PD7
PA0:PA2
PB5:PB7
PE4:PE7
Pin name
PC0:PC7
PD0:PD5
PA4:PA7
PB0:PB4
PE0:PE1
PF0:PF2
PA3
1)
1)
1)
1)
floating*
floating*
floating*
floating*
floating*
floating*
floating*
floating*
floating*
floating*
OR = 0
Input (DDR = 0)
floating*
floating*
pull-up with interrupt
pull-up with interrupt
pull-up with interrupt
pull-up with interrupt
pull-up with interrupt
2)
OR = 1
pull-up
pull-up
pull-up
pull-up
pull-up
open drain, high sink capability
open drain, high sink capability
open-drain
open-drain
open-drain
open-drain
open-drain
open-drain
open-drain
open-drain
open-drain
open-drain
OR = 0
Output (DDR = 1)
push-pull
push-pull
push-pull
push-pull
push-pull
push-pull
push-pull
push-pull
push-pull
push-pull
OR =1
3)