ATMEGA644P-20PU Atmel, ATMEGA644P-20PU Datasheet - Page 187
ATMEGA644P-20PU
Manufacturer Part Number
ATMEGA644P-20PU
Description
IC MCU AVR 64K FLASH 40-DIP
Manufacturer
Atmel
Series
AVR® ATmegar
Specifications of ATMEGA644P-20PU
Core Processor
AVR
Core Size
8-Bit
Speed
20MHz
Connectivity
I²C, SPI, UART/USART
Peripherals
Brown-out Detect/Reset, POR, PWM, WDT
Number Of I /o
32
Program Memory Size
64KB (32K x 16)
Program Memory Type
FLASH
Eeprom Size
2K x 8
Ram Size
4K x 8
Voltage - Supply (vcc/vdd)
2.7 V ~ 5.5 V
Data Converters
A/D 8x10b
Oscillator Type
Internal
Operating Temperature
-40°C ~ 85°C
Package / Case
40-DIP (0.600", 15.24mm)
Processor Series
ATMEGA64x
Core
AVR8
Data Bus Width
8 bit
Data Ram Size
4 KB
Interface Type
2-Wire/JTAG/SPI/USART
Maximum Clock Frequency
20 MHz
Number Of Programmable I/os
32
Number Of Timers
3
Maximum Operating Temperature
+ 85 C
Mounting Style
Through Hole
3rd Party Development Tools
EWAVR, EWAVR-BL
Development Tools By Supplier
ATAVRDRAGON, ATSTK500, ATSTK600, ATAVRISP2, ATAVRONEKIT
Minimum Operating Temperature
- 40 C
On-chip Adc
8-ch x 10-bit
For Use With
ATSTK600-TQFP44 - STK600 SOCKET/ADAPTER 44-TQFPATSTK600 - DEV KIT FOR AVR/AVR32770-1007 - ISP 4PORT ATMEL AVR MCU SPI/JTAGATAVRISP2 - PROGRAMMER AVR IN SYSTEM
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Company:
Part Number:
ATMEGA644P-20PU
Manufacturer:
Atmel
Quantity:
1 984
- Current page: 187 of 439
- Download datasheet (10Mb)
16.10 Multi-processor Communication Mode
8011O–AVR–07/10
Table 16-2.
Table 16-3.
The recommendations of the maximum receiver baud rate error was made under the assump-
tion that the Receiver and Transmitter equally divides the maximum total error.
There are two possible sources for the receivers baud rate error. The Receiver’s system clock
(XTAL) will always have some minor instability over the supply voltage range and the tempera-
ture range. When using a crystal to generate the system clock, this is rarely a problem, but for a
resonator the system clock may differ more than 2% depending of the resonators tolerance. The
second source for the error is more controllable. The baud rate generator can not always do an
exact division of the system frequency to get the baud rate wanted. In this case an UBRR value
that gives an acceptable low error can be used if possible.
Setting the Multi-processor Communication mode (MPCMn) bit in UCSRnA enables a filtering
function of incoming frames received by the USART Receiver. Frames that do not contain
address information will be ignored and not put into the receive buffer. This effectively reduces
the number of incoming frames that has to be handled by the CPU, in a system with multiple
MCUs that communicate via the same serial bus. The Transmitter is unaffected by the MPCMn
setting, but has to be used differently when it is a part of a system utilizing the Multi-processor
Communication mode.
If the Receiver is set up to receive frames that contain 5 to 8 data bits, then the first stop bit indi-
cates if the frame contains data or address information. If the Receiver is set up for frames with
nine data bits, then the ninth bit (RXB8n) is used for identifying address and data frames. When
# (Data+Parity Bit)
# (Data+Parity Bit)
10
10
D
D
5
6
7
8
9
5
6
7
8
9
Recommended Maximum Receiver Baud Rate Error for Normal Speed Mode
(U2Xn = 0)
Recommended Maximum Receiver Baud Rate Error for Double Speed Mode
(U2Xn = 1)
R
R
slow
slow
93.20
94.12
94.81
95.36
95.81
96.17
94.12
94.92
95.52
96.00
96.39
96.70
(%)
(%)
R
R
105.66
104.92
104,35
103.90
103.53
103.23
105.79
105.11
104.58
104.14
103.78
106.67
fast
fast
(%)
(%)
Max Total Error (%)
ATmega164P/324P/644P
Max Total Error (%)
+5.66/-5.88
+4.92/-5.08
+4.35/-4.48
+3.90/-4.00
+3.53/-3.61
+3.23/-3.30
+5.79/-5.88
+5.11/-5.19
+4.58/-4.54
+4.14/-4.19
+3.78/-3.83
+6.67/-6.8
Recommended Max
Recommended Max
Receiver Error (%)
Receiver Error (%)
±2.5
±2.0
±1.5
±1.5
±1.5
±1.0
±3.0
±2.5
±2.0
±2.0
±1.5
±1.5
187
Related parts for ATMEGA644P-20PU
Image
Part Number
Description
Manufacturer
Datasheet
Request
R
Part Number:
Description:
Manufacturer:
Atmel Corporation
Datasheet:
Part Number:
Description:
IC AVR MCU FLASH 64K 44-QFN
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
IC AVR MCU FLASH 64K 44TQFP
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
IC AVR MCU FLASH 64K 40DIP
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
MCU AVR 64K FLASH 20MHZ 44TQFP
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
MCU AVR 64K FLASH 20MHZ 44QFN
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
Atmega644 8-bit Avr Microcontroller With 64k Bytes In-system Programmable Flash
Manufacturer:
ATMEL Corporation
Datasheet:
Part Number:
Description:
Manufacturer:
Atmel Corporation
Datasheet:
Part Number:
Description:
Manufacturer:
ATMEL Corporation
Datasheet:
Part Number:
Description:
Manufacturer:
ATMEL Corporation
Datasheet:
Part Number:
Description:
IC AVR MCU 64K 16MHZ 5V 64TQFP
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
IC AVR MCU 64K 16MHZ 5V 64-QFN
Manufacturer:
Atmel
Datasheet: