C the number of bytes that can be transmitted per

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c The number of bytes that can be transmitted per transfer is unrestricted. c Each byte has to be followed by an Acknowledge bit. c Data is transferred with the Most Significant Bit (MSB) first. Reference : UM10204 - I2C Bus Specification & User Manual from NXP Semiconductors
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I2C Bus – Byte Format c 9-th pulse: – transmitter releases SDA – receiver must hold SDA low in order to ack. received data – slave must release SDA after ack. bit (allows master to end frame)
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I2C Bus – Arbitration c Arbitration refers to a portion of the protocol required only if more than one master will be used in the system. c A master may start a transfer only if the bus is free. Two masters may generate a valid START condition on the bus. c Arbitration is then required to determine which master will complete its transmission. Reference : UM10204 - I2C Bus Specification & User Manual from NXP Semiconductors
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I2C Bus – Data Transfer c After the START condition (S), a slave address is sent. c This address is 7 bits long followed by an eighth bit which is a data direction bit (R/W) — a ‘zero’ indicates a transmission (WRITE), a ‘one’ indicates a request for data (READ). c A data transfer is always terminated by a STOP condition (P) generated by the master. Reference : UM10204 - I2C Bus Specification & User Manual from NXP Semiconductors
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I2C Bus – Possible Data Transfer Formats Reference : UM10204 - I2C Bus Specification & User Manual from NXP Semiconductors
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Message protocols c I²C defines three basic types of message, each of which begins with a START and ends with a STOP: c Single message where a master writes data to a slave; c Single message where a master reads data from a slave; c Combined messages, where a master issues at least two reads and/or writes to one or more slaves.
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Message protocols c In a combined message, each read or write begins with a START and the slave address. After the first START, these are also called repeated START bits; repeated START bits are not preceded by STOP bits, which is how slaves know the next transfer is part of the same message.
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I2C Bus – Other evolved variants c SMBus – System Management Bus. c PMBus – Power Management Bus. c IPMI – Intelligent Platform Management Interface. Reference : UM10204 - I2C Bus Specification & User Manual from NXP Semiconductors
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c A Serial Peripheral Interface (SPI) system is a Master-Slave protocol. c SPI consists of one master device and one or more slave devices. c The master is defined as a microcontroller providing the SPI clock and the slave as any integrated circuit receiving the SPI clock from the master. c SPI is also called “four wire” serial bus and operates in full- duplex mode. c
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c The number of bytes that can be transmitted per transfer...

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