ATMEGA88-20MU Atmel, ATMEGA88-20MU Datasheet - Page 184
![no-image](/images/manufacturer_photos/0/0/78/atmel_sml.jpg)
ATMEGA88-20MU
Manufacturer Part Number
ATMEGA88-20MU
Description
IC AVR MCU 8K 20MHZ 5V 32-QFN
Manufacturer
Atmel
Series
AVR® ATmegar
Datasheets
1.ATAVRTS2080B.pdf
(378 pages)
2.ATMEGA48-20AU.pdf
(35 pages)
3.ATMEGA88-20MU.pdf
(33 pages)
Specifications of ATMEGA88-20MU
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
23
Program Memory Size
8KB (4K x 16)
Program Memory Type
FLASH
Eeprom Size
512 x 8
Ram Size
1K 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
32-VQFN Exposed Pad, 32-HVQFN, 32-SQFN, 32-DHVQFN
Package
32MLF EP
Device Core
AVR
Family Name
ATmega
Maximum Speed
20 MHz
Operating Supply Voltage
3.3|5 V
Data Bus Width
8 Bit
Number Of Programmable I/os
23
Interface Type
SPI/TWI/USART
On-chip Adc
8-chx10-bit
Number Of Timers
3
Processor Series
ATMEGA8x
Core
AVR8
Data Ram Size
1 KB
Maximum Clock Frequency
20 MHz
Maximum Operating Temperature
+ 85 C
Mounting Style
SMD/SMT
3rd Party Development Tools
EWAVR, EWAVR-BL
Development Tools By Supplier
ATAVRDRAGON, ATSTK500, ATSTK600, ATAVRISP2, ATAVRONEKIT, ATAVRTS2080A, ATASTK512-EK1-IND
Minimum Operating Temperature
- 40 C
A/d Inputs
8-Channel, 10-Bit
Cpu Speed
20 MIPS
Eeprom Memory
512 Bytes
Input Output
23
Interface
SPI/TWI/USART
Memory Type
Flash
Number Of Bits
8
Package Type
32-pin MLF
Programmable Memory
8K Bytes
Timers
2-8-bit, 1-16-bit
Voltage, Range
4.5-5.5 V
Controller Family/series
AVR MEGA
No. Of I/o's
23
Eeprom Memory Size
512Byte
Ram Memory Size
1KB
No. Of Timers
3
Rohs Compliant
Yes
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
- Current page: 184 of 378
- Download datasheet (8Mb)
19.7.6
19.7.7
19.8
19.8.1
184
Asynchronous Data Reception
ATmega48/88/168
Disabling the Receiver
Flushing the Receive Buffer
Asynchronous Clock Recovery
The UPEn bit is set if the next character that can be read from the receive buffer had a Parity
Error when received and the Parity Checking was enabled at that point (UPMn1 = 1). This bit is
valid until the receive buffer (UDRn) is read.
In contrast to the Transmitter, disabling of the Receiver will be immediate. Data from ongoing
receptions will therefore be lost. When disabled (that is, the RXENn is set to zero) the Receiver
will no longer override the normal function of the RxDn port pin. The Receiver buffer FIFO will be
flushed when the Receiver is disabled. Remaining data in the buffer will be lost
The receiver buffer FIFO will be flushed when the Receiver is disabled, that is, the buffer will be
emptied of its contents. Unread data will be lost. If the buffer has to be flushed during normal
operation, due to for instance an error condition, read the UDRn I/O location until the RXCn Flag
is cleared. The following code example shows how to flush the receive buffer.
Note:
The USART includes a clock recovery and a data recovery unit for handling asynchronous data
reception. The clock recovery logic is used for synchronizing the internally generated baud rate
clock to the incoming asynchronous serial frames at the RxDn pin. The data recovery logic sam-
ples and low pass filters each incoming bit, thereby improving the noise immunity of the
Receiver. The asynchronous reception operational range depends on the accuracy of the inter-
nal baud rate clock, the rate of the incoming frames, and the frame size in number of bits.
The clock recovery logic synchronizes internal clock to the incoming serial frames.
illustrates the sampling process of the start bit of an incoming frame. The sample rate is 16 times
the baud rate for Normal mode, and eight times the baud rate for Double Speed mode. The hor-
izontal arrows illustrate the synchronization variation due to the sampling process. Note the
larger time variation when using the Double Speed mode (U2Xn = 1) of operation. Samples
denoted zero are samples done when the RxDn line is idle (that is, no communication activity).
Assembly Code Example
C Code Example
USART_Flush:
void USART_Flush( void )
{
}
sbis UCSRnA, RXCn
ret
in
rjmp USART_Flush
unsigned char dummy;
while ( UCSRnA & (1<<RXCn) ) dummy = UDRn;
1.
See ”About Code Examples” on page 7.
r16, UDRn
(1)
(1)
2545S–AVR–07/10
Figure 19-5
Related parts for ATMEGA88-20MU
Image
Part Number
Description
Manufacturer
Datasheet
Request
R
![ATMEGA88-20AI](/photos/6/91/69154/313-32-tqfp_tmb.jpg)
Part Number:
Description:
IC MCU AVR 8K 5V 20MHZ 32-TQFP
Manufacturer:
Atmel
Datasheet:
![ATmega88](/images/manufacturer_photos/0/0/79/atmel_corporation_tmb.jpg)
Part Number:
Description:
Manufacturer:
Atmel Corporation
Datasheet:
![ATmega88 Automotive](/images/manufacturer_photos/0/0/79/atmel_corporation_tmb.jpg)
Part Number:
Description:
Manufacturer:
Atmel Corporation
Datasheet:
![ATMEGA88-15MZ](/photos/30/99/309943/qfn-32_tmb.jpg)
Part Number:
Description:
MCU AVR 8K FLASH 15MHZ 32-QFN
Manufacturer:
Atmel
Datasheet:
![ATMEGA88-20AU](/photos/6/91/69154/313-32-tqfp_tmb.jpg)
Part Number:
Description:
IC AVR MCU 8K 20MHZ 5V 32TQFP
Manufacturer:
Atmel
Datasheet:
![ATMEGA88-20PU](/photos/7/21/72189/453-28-dip_tmb.jpg)
Part Number:
Description:
IC AVR MCU 8K 20MHZ 5V 28DIP
Manufacturer:
Atmel
Datasheet:
![ATMEGA88-20AJ](/photos/6/91/69154/313-32-tqfp_tmb.jpg)
Part Number:
Description:
IC MCU AVR 8K 5V 20MHZ 32-TQFP
Manufacturer:
Atmel
Datasheet:
![ATMEGA88-20MI](/images/manufacturer_photos/0/0/78/atmel_tmb.jpg)
Part Number:
Description:
IC MCU AVR 8K 5V 20MHZ 32-QFN
Manufacturer:
Atmel
Datasheet:
![ATMEGA88-20MJ](/images/manufacturer_photos/0/0/78/atmel_tmb.jpg)
Part Number:
Description:
IC MCU AVR 8K 5V 20MHZ 32-QFN
Manufacturer:
Atmel
Datasheet:
![ATMEGA88-20PI](/photos/7/21/72189/453-28-dip_tmb.jpg)
Part Number:
Description:
IC MCU AVR 8K 5V 20MHZ 28-DIP
Manufacturer:
Atmel
Datasheet:
![ATMEGA88-20PJ](/photos/7/21/72189/453-28-dip_tmb.jpg)
Part Number:
Description:
IC MCU AVR 8K 5V 20MHZ 28-DIP
Manufacturer:
Atmel
Datasheet:
![ATMEGA88-20AUR](/images/manufacturer_photos/0/0/78/atmel_tmb.jpg)
Part Number:
Description:
MCU AVR 8K FLASH 20MHZ 32TQFP
Manufacturer:
Atmel
Datasheet:
![ATMEGA88-20MUR](/images/manufacturer_photos/0/0/78/atmel_tmb.jpg)
Part Number:
Description:
MCU AVR 8K FLASH 20MHZ 32QFN
Manufacturer:
Atmel
Datasheet: