1. Functional Overview > I
2
C Interface
31
Tsi578 User Manual
June 6, 2016
Integrated Device Technology
www.idt.com
— I
2
C Interface: Master interface
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Supports 7-bit device addressing
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Supports 0, 1, or 2-byte peripheral addressing
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Supports 0, 1, 2, 3, or 4-byte data transfers
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Reverts to slave mode if arbitration is lost
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Supports clock stretching by an external slave to limit bus speed to less than 100 kHz
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Handles timeouts and reports them through interrupts
— I
2
C Interface: Slave interface
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Slave address can be loaded from three sources: power-up signals, boot load from
EEPROM, or by software configuration
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Provides read and write accesses that are 32 bits in size to all Tsi578 registers
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Ignores General-Call accesses
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Ignores Start-Byte protocol
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Provides a status register for determination of Tsi578’s health
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Slave operation enabled/disabled through power-up signal, boot load from EEPROM, or
by software configuration
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Provides mailbox registers for communicating between maintenance software operating
on RapidIO based processors and external I
2
C masters
•
Supports I
2
C operations up to 100 kHz
•
Provides boot-time register initialization
— Supports 1- and 2-byte addressing of the EEPROM selected by power-up signal
— Verifies the number of registers to be loaded is legal before loading registers
— Supports up to 2K byte address space and up to 255 address/data pairs for register
configuration in 1-byte addressing mode, or up to 65 Kbyte address space and up to 8 K-1
address/data pairs in 2-byte addressing mode.
— Supports chaining to a different EEPROM and/or EEPROM address during initialization.
The I
2
C Interface does not support the following features:
•
START Byte protocol
— Tsi578 does not provide a START Byte in transactions it masters
— Tsi578 does not respond to START Bytes in transactions initiated by other devices. The
Tsi578 will respond to the repeated start following the start byte provided the 7-bit address
provided matches the Tsi578 device address.