AT32UC3B1256-Z1UR Atmel, AT32UC3B1256-Z1UR Datasheet - Page 224

• Manufacturer Part Number: AT32UC3B1256-Z1UR
• Description: MCU AVR32 256K FLASH 48-QFN
• Manufacturer: Atmel
• Series: AVR®32 UC3r

Specifications of AT32UC3B1256-Z1UR

• Package / Case: 48-QFN Exposed Pad
• Voltage - Supply (vcc/vdd): 1.65 V ~ 1.95 V
• Operating Temperature: -40°C ~ 85°C
• Speed: 60MHz
• Number Of I /o: 28
• Core Processor: AVR
• Program Memory Type: FLASH
• Ram Size: 32K x 8
• Program Memory Size: 256KB (256K x 8)
• Data Converters: A/D 6x10b
• Oscillator Type: Internal
• Peripherals: Brown-out Detect/Reset, DMA, POR, PWM, WDT
• Connectivity: I²C, IrDA, SPI, SSC, UART/USART, USB
• Core Size: 32-Bit
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -

19.10 Master Mode
19.10.1
19.10.2
Figure 19-5. Master Mode Typical Application Block Diagram
19.10.3
19.10.4
19.10.5
32059J–12/2010
Definition
Application Block Diagram
Programming Master Mode
Master Mode Clock Timing
Master Transmitter Mode
Rp: Pull up value as given by the I²C Standard
Host with
Interface
TWI
The Master is the device which starts a transfer, generates a clock and stops it.
The following registers have to be programmed before entering Master mode:
1. DADR (+ IADRSZ + IADR if a 10 bit device is addressed): The device address is used to
2. CKDIV + CHDIV + CLDIV: Determines clock waveform T
3. SVDIS: Disable the slave mode.
4. MSEN: Enable the master mode.
The TWI module monitors the state of the TWCK line as required by the I²C specification. The
counter that determines the TWCK T
is detected by the module on TWCK, not when the module begins releasing or driving the TWCK
line. Thus, the CWGR.CHDIV and CLDIV fields do not alone determine the overall TWCK
period; they merely determine the T
(T
tion and synchronization delay of TWCK from the pin back into the TWI module. The TWI
module does not attempt to compensate for these delays, so the overall TWI clock period is
given by T
After the master initiates a Start condition when writing into the Transmit Holding Register, THR,
it sends a 7-bit slave address, configured in the Master Mode register (DADR in MMR), to notify
the slave device. The bit following the slave address indicates the transfer direction, 0 in this
case (MREAD = 0 in MMR).
TWD
TWCK
rise
access slave devices in read or write mode.
Serial EEPROM
and T
Atmel TWI
Slave 1
high
fall
) are determined by the external circuitry on the TWCK pin as well as the propaga-
+T
fall
+T
low
+T
I²C RTC
Slave 2
rise
.
high
high
Controller
I²C LCD
Slave 3
or T
and T
low
low
duration is started whenever a high or low level
components, whereas the rise and fall times
I²C Temp.
Slave 4
Sensor
high
Rp
and T
Rp
low
.
AT32UC3B
VDD
224