AT89C51RE2-SLSUM Atmel, AT89C51RE2-SLSUM Datasheet - Page 77
![MCU 8BIT FLASH 2.7-5.5V 44-PLCC](/photos/6/70/67043/453-44-plcc_sml.jpg)
AT89C51RE2-SLSUM
Manufacturer Part Number
AT89C51RE2-SLSUM
Description
MCU 8BIT FLASH 2.7-5.5V 44-PLCC
Manufacturer
Atmel
Series
89Cr
Datasheet
1.AT89C51RE2-SLSUM.pdf
(187 pages)
Specifications of AT89C51RE2-SLSUM
Core Processor
8051
Core Size
8-Bit
Speed
60MHz
Connectivity
I²C, SPI, UART/USART
Peripherals
POR, PWM, WDT
Number Of I /o
34
Program Memory Size
128KB (128K x 8)
Program Memory Type
FLASH
Ram Size
8K x 8
Voltage - Supply (vcc/vdd)
2.7 V ~ 5.5 V
Oscillator Type
External
Operating Temperature
-40°C ~ 85°C
Package / Case
44-PLCC
Package
44PLCC
Device Core
8051
Family Name
89C
Maximum Speed
40 MHz
Operating Supply Voltage
3.3|5 V
Data Bus Width
8 Bit
Number Of Programmable I/os
34
Interface Type
SPI/TWI/UART
Number Of Timers
3
Processor Series
AT89x
Core
8051
Data Ram Size
8 KB
Maximum Clock Frequency
40 MHz
Maximum Operating Temperature
+ 85 C
Mounting Style
SMD/SMT
3rd Party Development Tools
PK51, CA51, A51, ULINK2
Development Tools By Supplier
AT89OCD-01
Minimum Operating Temperature
- 40 C
Cpu Family
89C
Device Core Size
8b
Frequency (max)
40MHz
Total Internal Ram Size
8KB
# I/os (max)
34
Number Of Timers - General Purpose
3
Operating Supply Voltage (typ)
3.3/5V
Operating Supply Voltage (max)
5.5V
Operating Supply Voltage (min)
2.7V
Instruction Set Architecture
CISC
Operating Temp Range
-40C to 85C
Operating Temperature Classification
Industrial
Mounting
Surface Mount
Pin Count
44
Package Type
PLCC
For Use With
AT89OCD-01 - USB EMULATOR FOR AT8XC51 MCUAT89STK-11 - KIT STARTER FOR AT89C51RX2
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
Eeprom Size
-
Data Converters
-
Lead Free Status / Rohs Status
Lead free / RoHS Compliant
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Company:
Part Number:
AT89C51RE2-SLSUM
Manufacturer:
HONEYWELL
Quantity:
101
Timer 2
Auto-Reload Mode
7663E–8051–10/08
The Timer 2 in the AT89C51RE2 is the standard C52 Timer 2.
It is a 16-bit timer/counter: the count is maintained by two eight-bit timer registers, TH2 and TL2
are cascaded. It is controlled by T2CON (Table 52) and T2MOD (Table 53) registers. Timer 2
operation is similar to Timer 0 and Timer 1.C/T2 selects F
T2 (counter operation) as the timer clock input. Setting TR2 allows TL2 to increment by the
selected input.
Timer 2 has 3 operating modes: capture, autoreload and Baud Rate Generator. These modes
are selected by the combination of RCLK, TCLK and CP/RL2 (T2CON).
Refer to the Atmel 8-bit Microcontroller Hardware description for the description of Capture and
Baud Rate Generator Modes.
Timer 2 includes the following enhancements:
•
•
The auto-reload mode configures Timer 2 as a 16-bit timer or event counter with automatic
reload. If DCEN bit in T2MOD is cleared, Timer 2 behaves as in 80C52 (refer to the Atmel C51
Microcontroller Hardware description). If DCEN bit is set, Timer 2 acts as an Up/down
timer/counter as shown in Figure 28. In this mode the T2EX pin controls the direction of count.
When T2EX is high, Timer 2 counts up. Timer overflow occurs at FFFFh which sets the TF2 flag
and generates an interrupt request. The overflow also causes the 16-bit value in RCAP2H and
RCAP2L registers to be loaded into the timer registers TH2 and TL2.
When T2EX is low, Timer 2 counts down. Timer underflow occurs when the count in the timer
registers TH2 and TL2 equals the value stored in RCAP2H and RCAP2L registers. The under-
flow sets TF2 flag and reloads FFFFh into the timer registers.
The EXF2 bit toggles when Timer 2 overflows or underflows according to the direction of the
count. EXF2 does not generate any interrupt. This bit can be used to provide 17-bit resolution.
Auto-reload mode with up or down counter
Programmable clock-output
OSC
/12 (timer operation) or external pin
AT89C51RE2
77