ATMEGA8-16AI SL383 Atmel, ATMEGA8-16AI SL383 Datasheet - Page 169

• Manufacturer Part Number: ATMEGA8-16AI SL383
• Description: Semiconductors and Actives, Microprocessors, Microcontrollers
• Manufacturer: Atmel

Overview of the
TWI Module
SCL and SDA Pins
2486W–AVR–02/10
The TWI module is comprised of several submodules, as shown in
in a thick line are accessible through the AVR data bus.
Figure 76. Overview of the TWI Module
These pins interface the AVR TWI with the rest of the MCU system. The output drivers contain a
slew-rate limiter in order to conform to the TWI specification. The input stages contain a spike
suppression unit removing spikes shorter than 50 ns. Note that the internal pull-ups in the AVR
pads can be enabled by setting the PORT bits corresponding to the SCL and SDA pins, as
explained in the I/O Port section. The internal pull-ups can in some systems eliminate the need
for external ones.
Slew-rate
Address Match Unit
Arbitration detection
Control
START / STOP
Address Comparator
Address Register
Control
SCL
(TWAR)
Spike
Filter
Bus Interface Unit
Spike Suppression
Address/Data Shift
Register (TWDR)
Slew-rate
Control
SDA
Status Register
Ack
Spike
Filter
(TWSR)
State Machine and
Control Unit
Status control
Bit Rate Generator
Figure
Control Register
Bit Rate Register
Prescaler
(TWCR)
(TWBR)
ATmega8(L)
76. All registers drawn
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