ST7DALIF2 STMicroelectronics, ST7DALIF2 Datasheet - Page 62

• Manufacturer Part Number: ST7DALIF2
• Description: 8-BIT MCU WITH SINGLE VOLTAGE FLASH MEMORY, DATA EEPROM, ADC, TIMERS, SPI
• Manufacturer: STMicroelectronics

Specifications of ST7DALIF2

• 8 Kbytes Single Voltage Flash Program Memory With Read-out Protection, In-circuit Programming And In-application Programming (icp And Iap). 10k Write/erase Cycles Guaranteed, Data Retention: 20 years at 55°C.
• 256 Bytes Data Eeprom With Read-out Protection. 300k Write/erase Cycles Guaranteed, Data Retention: 20 years at 55°C.
• Clock Sources: Internal 1% RC oscillator, crystal/ceramic resonator or external clock
• Five Power Saving Modes: Halt, Active-Halt, Wait and Slow, Auto Wake Up From Halt

I/O ports
Caution:
12.2.2
62/171
When enabling/disabling an external interrupt by setting/resetting the related OR register bit,
a spurious interrupt is generated if the pin level is low and its edge sensitivity includes
falling/rising edge. This is due to the edge detector input which is switched to '1' when the
external interrupt is disabled by the OR register.
To avoid this unwanted interrupt, a "safe" edge sensitivity (rising edge for enabling and
falling edge for disabling) has to be selected before changing the OR register bit and
configuring the appropriate sensitivity again.
In case a pin level change occurs during these operations (asynchronous signal input), as
interrupts are generated according to the current sensitivity, it is advised to disable all
interrupts before and to reenable them after the complete previous sequence in order to
avoid an external interrupt occurring on the unwanted edge.
This corresponds to the following steps:
1. To enable an external interrupt:
2. To disable an external interrupt:
Output modes
Setting the DDRx bit selects output mode. Writing to the DR bits applies a digital value to the
I/O through the latch. Reading the DR bits returns the previously stored value.
If an OR bit is available, different output modes can be selected by software: push-pull or
open-drain. Refer to I/O Port Implementation section for configuration.
Table 24.
– set the interrupt mask with the SIM instruction (in cases where a pin level change
– select rising edge
– enable the external interrupt through the OR register
– select the desired sensitivity if different from rising edge
– reset the interrupt mask with the RIM instruction (in cases where a pin level change
– set the interrupt mask with the SIM instruction SIM (in cases where a pin level change
– select falling edge
– disable the external interrupt through the OR register
– select rising edge
– reset the interrupt mask with the RIM instruction (in cases where a pin level change
could occur)
could occur)
could occur)
could occur)
DR
0
1
DR value and output pin status
Push-pull
V
V
OH
OL
Open-drain
Floating
V
OL
ST7DALIF2