SLV_DISABLED_WHILE_BUSY=INACTIVE, SLV_RX_DATA_LOST=INACTIVE, IC_EN=DISABLED
I2C Enable Status Register
The register is used to report the DW_apb_i2c hardware status when the IC_ENABLE[0] register is set from 1 to 0; that is, when DW_apb_i2c is disabled.
If IC_ENABLE[0] has been set to 1, bits 2:1 are forced to 0, and bit 0 is forced to 1.
If IC_ENABLE[0] has been set to 0, bits 2:1 is only be valid as soon as bit 0 is read as ‘0’.
Note: When IC_ENABLE[0] has been set to 0, a delay occurs for bit 0 to be read as 0 because disabling the DW_apb_i2c depends on I2C bus activities.
| IC_EN | ic_en Status. This bit always reflects the value driven on the output port ic_en. - When read as 1, DW_apb_i2c is deemed to be in an enabled state. - When read as 0, DW_apb_i2c is deemed completely inactive. Note: The CPU can safely read this bit anytime. When this bit is read as 0, the CPU can safely read SLV_RX_DATA_LOST (bit 2) and SLV_DISABLED_WHILE_BUSY (bit 1). Reset value: 0x0 0 (DISABLED): I2C disabled 1 (ENABLED): I2C enabled |
| SLV_DISABLED_WHILE_BUSY | Slave Disabled While Busy (Transmit, Receive). This bit indicates if a potential or active Slave operation has been aborted due to the setting bit 0 of the IC_ENABLE register from 1 to 0. This bit is set when the CPU writes a 0 to the IC_ENABLE register while: (a) DW_apb_i2c is receiving the address byte of the Slave-Transmitter operation from a remote master; OR, (b) address and data bytes of the Slave-Receiver operation from a remote master. When read as 1, DW_apb_i2c is deemed to have forced a NACK during any part of an I2C transfer, irrespective of whether the I2C address matches the slave address set in DW_apb_i2c (IC_SAR register) OR if the transfer is completed before IC_ENABLE is set to 0 but has not taken effect. Note: If the remote I2C master terminates the transfer with a STOP condition before the DW_apb_i2c has a chance to NACK a transfer, and IC_ENABLE[0] has been set to 0, then this bit will also be set to 1. When read as 0, DW_apb_i2c is deemed to have been disabled when there is master activity, or when the I2C bus is idle. Note: The CPU can safely read this bit when IC_EN (bit 0) is read as 0. Reset value: 0x0 0 (INACTIVE): Slave is disabled when it is idle 1 (ACTIVE): Slave is disabled when it is active |
| SLV_RX_DATA_LOST | Slave Received Data Lost. This bit indicates if a Slave-Receiver operation has been aborted with at least one data byte received from an I2C transfer due to the setting bit 0 of IC_ENABLE from 1 to 0. When read as 1, DW_apb_i2c is deemed to have been actively engaged in an aborted I2C transfer (with matching address) and the data phase of the I2C transfer has been entered, even though a data byte has been responded with a NACK. Note: If the remote I2C master terminates the transfer with a STOP condition before the DW_apb_i2c has a chance to NACK a transfer, and IC_ENABLE[0] has been set to 0, then this bit is also set to 1. When read as 0, DW_apb_i2c is deemed to have been disabled without being actively involved in the data phase of a Slave-Receiver transfer. Note: The CPU can safely read this bit when IC_EN (bit 0) is read as 0. Reset value: 0x0 0 (INACTIVE): Slave RX Data is not lost 1 (ACTIVE): Slave RX Data is lost |