ATmega1281R231 Atmel Corporation, ATmega1281R231 Datasheet - Page 264
![no-image](/images/manufacturer_photos/0/0/79/atmel_corporation_sml.jpg)
ATmega1281R231
Manufacturer Part Number
ATmega1281R231
Description
Manufacturer
Atmel Corporation
Specifications of ATmega1281R231
Flash (kbytes)
128 Kbytes
Max. Operating Frequency
16 MHz
Max I/o Pins
54
Spi
3
Twi (i2c)
1
Uart
2
Adc Channels
8
Adc Resolution (bits)
10
Adc Speed (ksps)
15
Analog Comparators
1
Crypto Engine
AES
Sram (kbytes)
8
Eeprom (bytes)
4096
Operating Voltage (vcc)
1.8 to 3.6
Timers
6
Frequency Band
2.4 GHz
Max Data Rate (mb/s)
2
Antenna Diversity
Yes
External Pa Control
Yes
Power Output (dbm)
3
Receiver Sensitivity (dbm)
-101
Receive Current Consumption (ma)
13.2
Transmit Current Consumption (ma)
14.4
Link Budget (dbm)
104
- Current page: 264 of 448
- Download datasheet (8Mb)
24.7.5
Table 24-6.
24.7.6
2549N–AVR–05/11
Status Code
(TWSR)
Prescaler Bits
are 0
0xF8
0x00
Miscellaneous States
Combining Several TWI Modes
Status of the 2-wire Serial Bus
and 2-wire Serial Interface Hard-
ware
No relevant state information
available; TWINT = “0”
Bus error due to an illegal
START or STOP condition
Miscellaneous States
Figure 24-18. Formats and States in the Slave Transmitter Mode
There are two status codes that do not correspond to a defined TWI state, see
Status 0xF8 indicates that no relevant information is available because the TWINT Flag is not
set. This occurs between other states, and when the TWI is not involved in a serial transfer.
Status 0x00 indicates that a bus error has occurred during a 2-wire Serial Bus transfer. A bus
error occurs when a START or STOP condition occurs at an illegal position in the format frame.
Examples of such illegal positions are during the serial transfer of an address byte, a data byte,
or an acknowledge bit. When a bus error occurs, TWINT is set. To recover from a bus error, the
TWSTO Flag must set and TWINT must be cleared by writing a logic one to it. This causes the
TWI to enter the not addressed Slave mode and to clear the TWSTO Flag (no other bits in
TWCR are affected). The SDA and SCL lines are released, and no STOP condition is
transmitted.
In some cases, several TWI modes must be combined in order to complete the desired action.
Consider for example reading data from a serial EEPROM. Typically, such a transfer involves
the following steps:
1. The transfer must be initiated.
2. The EEPROM must be instructed what location should be read.
3. The reading must be performed.
4. The transfer must be finished.
Reception of the own
slave address and one or
more data bytes
Arbitration lost as master
and addressed as slave
Last data byte transmitted.
Switched to not addressed
slave (TWEA = '0')
To/from TWDR
No TWDR action
No TWDR action
From master to slave
From slave to master
S
Application Software Response
SLA
STA
0
ATmega640/1280/1281/2560/2561
No TWCR action
STO
R
1
DATA
To TWCR
$A8
$B0
TWINT
A
A
n
1
A
TWEA
X
DATA
Any number of data bytes
and their associated acknowledge bits
This number (contained in TWSR) corresponds
to a defined state of the Two-Wire Serial Bus. The
prescaler bits are zero or masked to zero
Next Action Taken by TWI Hardware
Wait or proceed current transfer
Only the internal hardware is affected, no STOP condi-
tion is sent on the bus. In all cases, the bus is released
and TWSTO is cleared.
$B8
A
DATA
$C0
$C8
A
A
Table
P or S
All 1's
24-6.
P or S
264
Related parts for ATmega1281R231
Image
Part Number
Description
Manufacturer
Datasheet
Request
R
![ATMEGA128](/images/manufacturer_photos/0/0/79/atmel_corporation_tmb.jpg)
Part Number:
Description:
Manufacturer:
ATMEL Corporation
Datasheet:
![ATMEGA128-8AC](/images/manufacturer_photos/0/0/79/atmel_corporation_tmb.jpg)
Part Number:
Description:
Microcontroller with 128K bytes In-system programmable flash, 8 MHz, power supply =2.7 - 5.5V
Manufacturer:
ATMEL Corporation
Datasheet:
![ATMEGA128-8AI](/images/manufacturer_photos/0/0/79/atmel_corporation_tmb.jpg)
Part Number:
Description:
8-bit Microcontroller with 128K Bytes In-System Programmable Flash
Manufacturer:
ATMEL Corporation
Datasheet:
![ATMEGA128RFA1-ZU](/photos/12/13/121326/313-64-qfn_tmb.jpg)
Part Number:
Description:
IC AVR MCU 2.4GHZ XCEIVER 64QFN
Manufacturer:
Atmel
Datasheet:
![ATMEGA328P-20PU](/images/manufacturer_photos/0/0/78/atmel_tmb.jpg)
Part Number:
Description:
Manufacturer:
Atmel
Datasheet:
![ATMEGA64RZAV-10PU](/photos/14/18/141872/atmega64rzav-10pu_tmb.jpg)
Part Number:
Description:
MCU ATMEGA644/AT86RF230 40-DIP
Manufacturer:
Atmel
Datasheet:
![ATMEGA64RZAPV-10MU](/photos/12/13/121326/313-64-qfn_tmb.jpg)
Part Number:
Description:
BUNDLE ATMEGA644P/AT86RF230 QFN
Manufacturer:
Atmel
Datasheet:
![ATMEGA64RZAPV-10AU](/photos/6/70/67042/313-44-tqfp_tmb.jpg)
Part Number:
Description:
BUNDLE ATMEGA644P/AT86RF230 TQFP
Manufacturer:
Atmel
Datasheet:
![ATMEGA128RZAV-8AU](/photos/12/13/121332/313-64-tqfp_tmb.jpg)
Part Number:
Description:
MCU ATMEGA1281/AT86RF230 64-TQFP
Manufacturer:
Atmel
Datasheet:
![ATMEGA168PA-PU](/photos/19/6/190669/ge28pdip05-40_tmb.jpg)
Part Number:
Description:
MCU, 8BIT, AVR, 16K FLASH, 28PDIP
Manufacturer:
Atmel
Datasheet:
![MIKROE-459](/photos/40/80/408077/mcu_card_atmega_tmb.jpg)
Part Number:
Description:
Microcontroller Modules MCU CARD BIGAVR6 100P W/ ATMEGA2560
Manufacturer:
mikroElektronika