AT89C51RB2-3CSIM Atmel, AT89C51RB2-3CSIM Datasheet - Page 56

• Manufacturer Part Number: AT89C51RB2-3CSIM
• Description: IC 8051 MCU FLASH 16K 40DIP
• Manufacturer: Atmel
• Series: 89Cr

Specifications of AT89C51RB2-3CSIM

• Core Processor: 8051
• Core Size: 8-Bit
• Speed: 60MHz
• Connectivity: SPI, UART/USART
• Peripherals: POR, PWM, WDT
• Number Of I /o: 32
• Program Memory Size: 16KB (16K x 8)
• Program Memory Type: FLASH
• Ram Size: 1.25K x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Oscillator Type: External
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 40-DIP (0.600", 15.24mm)
• Data Bus Width: 8 bit
• Data Ram Size: 1.25 KB
• Interface Type: SPI, UART
• Maximum Clock Frequency: 40 MHz
• Number Of Programmable I/os: 32
• Number Of Timers: 3
• Operating Supply Voltage: 5 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: Through Hole
• Minimum Operating Temperature: - 40 C
• For Use With: AT89STK-11 - KIT STARTER FOR AT89C51RX2
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Eeprom Size: -
• Data Converters: -
• Lead Free Status / Rohs Status: No

Registers
56
AT89C51RB2/RC2
A low-priority interrupt can be interrupted by a high-priority interrupt, but not by another
low-priority interrupt. A high-priority interrupt can’t be interrupted by any other interrupt
source.
Table 43. Priority Level Bit Values
If two interrupt requests of different priority levels are received simultaneously, the
request of higher-priority level is serviced. If interrupt requests of the same priority level
are received simultaneously, an internal polling sequence determines which request is
serviced. Thus within each priority level there is a second priority structure determined
by the polling sequence.
IPH. x
0
0
1
1
IPL. x
0
1
0
1
Interrupt Level Priority
3 (Highest)
0 (Lowest)
1
2
4180E–8051–10/06