ST7LITE25F2 STMicroelectronics, ST7LITE25F2 Datasheet - Page 36

• Manufacturer Part Number: ST7LITE25F2
• Description: 8-BIT MCU WITH SINGLE VOLTAGE FLASH MEMORY, DATA EEPROM, ADC, TIMERS, SPI
• Manufacturer: STMicroelectronics

Specifications of ST7LITE25F2

• 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.
• 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

ST7LITE2
INTERRUPTS (Cont’d)
EXTERNAL INTERRUPT CONTROL REGISTER
(EICR)
Read/Write
Reset Value: 0000 0000 (00h)
Bit 7:6 = IS3[1:0] ei3 sensitivity
These bits define the interrupt sensitivity for ei3
(Port B0) according to
Bit 5:4 = IS2[1:0] ei2 sensitivity
These bits define the interrupt sensitivity for ei2
(Port B3) according to
Bit 3:2 = IS1[1:0] ei1 sensitivity
These bits define the interrupt sensitivity for ei1
(Port A7) according to
Bit 1:0 = IS0[1:0] ei0 sensitivity
These bits define the interrupt sensitivity for ei0
(Port A0) according to
Notes:
1.These 8 bits can be written only when the I bit in
the CC register is set.
2. Changing the sensitivity of a particular external
interrupt clears this pending interrupt. This can be
used to clear unwanted pending interrupts. Refer
to section “External Interrupt Function” on
page 46.
Table 6. Interrupt Sensitivity Bits
.
36/133
1
ISx1 ISx0
IS31
0
0
1
1
7
IS30
0
1
0
1
IS21
External Interrupt Sensitivity
IS20
Falling edge & low level
Rising and falling edge
Table
Table
Table
Table
Falling edge only
Rising edge only
IS11
6.
6.
6.
6.
IS10
IS01
IS00
0
EXTERNAL INTERRUPT SELECTION REGIS-
TER (EISR)
Read/Write
Reset Value: 0000 1100 (0Ch)
Bit 7:6 = ei3[1:0] ei3 pin selection
These bits are written by software. They select the
Port B I/O pin used for the ei3 external interrupt ac-
cording to the table below.
External Interrupt I/O pin selection
Note:
1. Reset State
Bits 5:4 = ei2[1:0] ei2 pin selection
These bits are written by software. They select the
Port B I/O pin used for the ei2 external interrupt ac-
cording to the table below.
External Interrupt I/O pin selection
Notes:
1. Reset State
2. PB4 cannot be used as an external interrupt in
HALT mode.
ei31
7
ei31
ei21
0
0
1
0
0
1
1
ei30
ei30
ei20
ei21
0
1
0
0
1
0
1
ei20
ei11
I/O Pin
I/O Pin
PB0
PB3
PB4
ei10
PB1
PB2
PB5
PB6
1)
1)
2)
ei01
ei00
0