ATMEGA32-16PU Atmel, ATMEGA32-16PU Datasheet - Page 157

• Manufacturer Part Number: ATMEGA32-16PU
• Description: IC AVR MCU 32K 16MHZ 5V 40DIP
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA32-16PU

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 16MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 32
• Program Memory Size: 32KB (16K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 1K x 8
• Ram Size: 2K x 8
• Voltage - Supply (vcc/vdd): 4.5 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: ATMEGA32x
• Core: AVR8
• Data Bus Width: 8 bit
• Data Ram Size: 2 KB
• Interface Type: 2-Wire/SPI/USART
• Maximum Clock Frequency: 16 MHz
• Number Of Programmable I/os: 32
• Number Of Timers: 3
• Operating Supply Voltage: 4.5 V to 5.5 V
• 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
• A/d Inputs: 8-Channel, 10-Bit
• Cpu Speed: 16 MIPS
• Eeprom Memory: 1K Bytes
• Input Output: 32
• Interface: 2-Wire/SPI/USART
• Memory Type: Flash
• Number Of Bits: 8
• Package Type: 40-pin PDIP
• Programmable Memory: 32K Bytes
• Timers: 2-8-bit, 1-16-bit
• Voltage, Range: 4.5-5.5 V
• Data Rom Size: 1024 B
• Height: 4.83 mm
• Length: 52.58 mm
• Supply Voltage (max): 5.5 V
• Supply Voltage (min): 4.5 V
• Width: 13.97 mm
• Controller Family/series: AVR MEGA
• No. Of I/o's: 32
• Eeprom Memory Size: 1024Byte
• Ram Memory Size: 2KB
• Rohs Compliant: Yes
• For Use With: ATSTK524 - KIT STARTER ATMEGA32M1/MEGA32C1ATSTK600-TQFP32 - STK600 SOCKET/ADAPTER 32-TQFPATSTK600-TQFP44 - STK600 SOCKET/ADAPTER 44-TQFPATSTK600-DIP40 - STK600 SOCKET/ADAPTER 40-PDIP770-1007 - ISP 4PORT ATMEL AVR MCU SPI/JTAGATAVRDRAGON - KIT DRAGON 32KB FLASH MEM AVRATAVRISP2 - PROGRAMMER AVR IN SYSTEMATJTAGICE2 - AVR ON-CHIP D-BUG SYSTEMATSTK500 - PROGRAMMER AVR STARTER KIT
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Read Access
USART Register
Description
USART I/O Data Register –
UDR
2503G–AVR–11/04
Doing a read access to the UBRRH or the UCSRC Register is a more complex opera-
tion. However, in most applications, it is rarely necessary to read any of these registers.
The read access is controlled by a timed sequence. Reading the I/O location once
returns the UBRRH Register contents. If the register location was read in previous sys-
tem clock cycle, reading the register in the current clock cycle will return the UCSRC
contents. Note that the timed sequence for reading the UCSRC is an atomic operation.
Interrupts must therefore be controlled (for example by disabling interrupts globally) dur-
ing the read operation.
The following code example shows how to read the UCSRC Register contents.
Note:
The assembly code example returns the UCSRC value in r16.
Reading the UBRRH contents is not an atomic operation and therefore it can be read as
an ordinary register, as long as the previous instruction did not access the register
location.
The USART Transmit Data Buffer Register and USART Receive Data Buffer Registers
share the same I/O address referred to as USART Data Register or UDR. The Transmit
Data Buffer Register (TXB) will be the destination for data written to the UDR Register
location. Reading the UDR Register location will return the contents of the Receive Data
Buffer Register (RXB).
For 5-, 6-, or 7-bit characters the upper unused bits will be ignored by the Transmitter
and set to zero by the Receiver.
Bit
Read/Write
Initial Value
Assembly Code Example
C Code Example
USART_ReadUCSRC:
unsigned char USART_ReadUCSRC( void )
{
}
; Read UCSRC
in
in
ret
unsigned char ucsrc;
/* Read UCSRC */
ucsrc = UBRRH;
ucsrc = UCSRC;
return ucsrc;
1. See “About Code Examples” on page 5.
r16,UBRRH
r16,UCSRC
R/W
7
0
(1)
R/W
6
0
(1)
R/W
5
0
R/W
4
0
RXB[7:0]
TXB[7:0]
R/W
3
0
R/W
2
0
ATmega32(L)
R/W
1
0
R/W
0
0
UDR (Read)
UDR (Write)
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