AT89S8253 Atmel Corporation, AT89S8253 Datasheet - Page 31

• Manufacturer Part Number: AT89S8253
• Manufacturer: Atmel Corporation

Specifications of AT89S8253

• Flash (kbytes): 12 Kbytes
• Max. Operating Frequency: 24 MHz
• Cpu: 8051-12C
• Max I/o Pins: 32
• Spi: 1
• Uart: 1
• Sram (kbytes): 0.25
• Eeprom (bytes): 2048
• Operating Voltage (vcc): 2.7 to 5.5
• Timers: 3
• Isp: SPI
• Watchdog: Yes

Table 15-1.
Table 15-2.
3286P–MICRO–3/10
Interrupt
System Reset
External Interrupt 0
Timer 0 Overflow
External Interrupt 1
Timer 1 Overflow
Serial Port
IE Address = A8H
Bit Addressable
Symbol
EA
–
ET2
ES
ET1
EX1
ET0
EX0
User software should never write 1s to reserved bits, because they may be used in future AT89 products.
Symbol
PT2
PS
PT1
PX1
PT0
PX0
IP = B8H
Bit Addressable
Bit
Enable Bit = 1 enables the interrupt, 0 disables the interrupt.
Position
IE.7
IE.6
IE.4
IE.2
IE.0
IE.5
IE.3
IE.1
EA
Function
Timer 2 Interrupt Priority Low
Serial Port Interrupt Priority Low
Timer 1 Interrupt Priority Low
External Interrupt 1 Priority Low
Timer 0 Interrupt Priority Low
External Interrupt 0 Priority Low
Interrupt Enable (IE) Register
IP
– Interrupt Priority Register
–
7
Function
Disables all interrupts. If EA = 0, no interrupt is acknowledged. If EA = 1, each interrupt source is individually
enabled or disabled by setting or clearing its enable bit.
Reserved.
Timer 2 interrupt enable bit.
Timer 1 interrupt enable bit.
External interrupt 1 enable bit.
Timer 0 interrupt enable bit.
External interrupt 0 enable bit.
SPI and UART interrupt enable bit.
–
–
6
ET2
PT2
5
Source
RST or POR
IE0
TF0
IE1
TF1
RI or TI or SPIF
ES
PS
4
ET1
PT1
3
EX1
PX1
2
Reset Value = 0X00 0000B
Reset Value = XX00 0000B
ET0
PT0
1
Vector Address
0000H
0003H
000BH
0013H
001BH
0023H
AT89S8253
EX0
PX0
0
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