Address: Base address + 8h offsetBit 7 6 5 4 3 2 1 0Read FACK ALERTEN SIICAEN TCKSEL SLTF SHTF1 SHTF2 SHTF2IEWrite w1c w1cReset 0 0 0 0 0 0 0 0I2Cx_SMB field descriptionsField Description7FACKFast NACK/ACK EnableFor SMBus packet error checking, the CPU must be able to issue an ACK or NACK according to the resultof receiving data byte.0 An ACK or NACK is sent on the following receiving data byte1 Writing 0 to TXAK after receiving a data byte generates an ACK. Writing 1 to TXAK after receiving adata byte generates a NACK.6ALERTENSMBus Alert Response Address EnableEnables or disables SMBus alert response address matching.NOTE: After the host responds to a device that used the alert response address, you must use softwareto put the device's address on the bus. The alert protocol is described in the SMBus specification.0 SMBus alert response address matching is disabled1 SMBus alert response address matching is enabled5SIICAENSecond I2C Address EnableEnables or disables SMBus device default address.0 I2C address register 2 matching is disabled1 I2C address register 2 matching is enabled4TCKSELTimeout Counter Clock SelectSelects the clock source of the timeout counter.0 Timeout counter counts at the frequency of the I2C module clock / 641 Timeout counter counts at the frequency of the I2C module clock3SLTFSCL Low Timeout FlagThis bit is set when the SLT register (consisting of the SLTH and SLTL registers) is loaded with a non-zerovalue (LoValue) and an SCL low timeout occurs. Software clears this bit by writing a logic 1 to it.NOTE: The low timeout function is disabled when the SLT register's value is 0.0 No low timeout occurs1 Low timeout occurs2SHTF1SCL High Timeout Flag 1This read-only bit sets when SCL and SDA are held high more than clock × LoValue / 512, which indicatesthe bus is free. This bit is cleared automatically.0 No SCL high and SDA high timeout occurs1 SCL high and SDA high timeout occursTable continues on the next page...Memory map/register definitionKL27 Sub-Family Reference Manual , Rev. 5, 01/2016624 Freescale Semiconductor, Inc.
