ATTINY48-MMU Atmel, ATTINY48-MMU Datasheet - Page 145

• Manufacturer Part Number: ATTINY48-MMU
• Description: MCU AVR 5K FLASH 12MHZ 28-QFN
• Manufacturer: Atmel
• Series: AVR® ATtinyr

Specifications of ATTINY48-MMU

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 12MHz
• Connectivity: I²C, SPI
• Peripherals: Brown-out Detect/Reset, POR, WDT
• Number Of I /o: 24
• Program Memory Size: 4KB (2K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 64 x 8
• Ram Size: 256 x 8
• Voltage - Supply (vcc/vdd): 1.8 V ~ 5.5 V
• Data Converters: A/D 6x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 28-VQFN Exposed Pad, 28-HVQFN, 28-SQFN, 28-DHVQFN
• Processor Series: ATTINY4x
• Core: AVR8
• Data Bus Width: 8 bit
• Data Ram Size: 256 B
• Interface Type: 2-Wire, I2S, SPI
• Maximum Clock Frequency: 12 MHz
• Number Of Programmable I/os: 24
• Number Of Timers: 2
• 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
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 10 bit, 6 Channel
• Package: 28VQFN EP
• Device Core: AVR
• Family Name: ATtiny
• Maximum Speed: 12 MHz
• Operating Supply Voltage: 2.5|3.3|5 V
• For Use With: ATAVRDRAGON - KIT DRAGON 32KB FLASH MEM AVR
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

8008G–AVR–04/11
Figure 15-13. Data Transfer in Master Receiver Mode
A START condition is sent by writing the following value to TWCR:
TWEN must be written to one to enable the 2-wire Serial Interface, TWSTA must be written to
one to transmit a START condition and TWINT must be set to clear the TWINT Flag. The TWI
will then test the 2-wire Serial Bus and generate a START condition as soon as the bus
becomes free. After a START condition has been transmitted, the TWINT Flag is set by hard-
ware, and the status code in TWSR will be 0x08 (See
SLA+R must be transmitted. This is done by writing SLA+R to TWDR. Thereafter the TWINT bit
should be cleared (by writing it to one) to continue the transfer. This is accomplished by writing
the following value to TWCR:
When SLA+R have been transmitted and an acknowledgement bit has been received, TWINT is
set again and a number of status codes in TWSR are possible. Possible status codes in Master
mode are 0x38, 0x40, or 0x48. The appropriate action to be taken for each of these status codes
is detailed in
Flag is set high by hardware. This scheme is repeated until the last byte has been received.
After the last byte has been received, the MR should inform the ST by sending a NACK after the
last received data byte. The transfer is ended by generating a STOP condition or a repeated
START condition. A STOP condition is generated by writing the following value to TWCR:
A REPEATED START condition is generated by writing the following value to TWCR:
SDA
SCL
TWCR
value
TWCR
value
TWCR
value
TWCR
value
Table
Device 1
RECEIVER
TWINT
TWINT
TWINT
TWINT
MASTER
1
1
1
1
15-3. Received data can be read from the TWDR Register when the TWINT
TWEA
TWEA
TWEA
TWEA
TRANSMITTER
X
X
X
X
Device 2
SLAVE
TWSTA
TWSTA
TWSTA
TWSTA
1
0
0
1
Device 3
TWSTO
TWSTO
TWSTO
TWSTO
0
0
1
0
........
Table
TWWC
TWWC
TWWC
TWWC
X
X
X
X
Device n
15-2). In order to enter MR mode,
V
TWEN
TWEN
TWEN
TWEN
CC
1
1
1
1
ATtiny48/88
R1
–
0
–
0
–
0
–
0
R2
TWIE
TWIE
TWIE
TWIE
X
X
X
X
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