ic_raw_intr_stat
I2C Raw Interrupt Status Register
Unlike the IC_INTR_STAT register, these bits are not masked so they
always show the true status of the I2C module.
Module Instance | Base Address | Register Address |
---|---|---|
i_i2c_0_i2c | 0xFFC02200 | 0xFFC02234 |
i_i2c_1_i2c | 0xFFC02300 | 0xFFC02334 |
Offset: 0x34
Access: RO
Important: The value of a reserved bit must be maintained in software. When you modify registers containing reserved bit fields, you must use a read-modify-write operation to preserve state and prevent indeterminate system behavior.
Bit Fields | |||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
31 | 30 | 29 | 28 | 27 | 26 | 25 | 24 | 23 | 22 | 21 | 20 | 19 | 18 | 17 | 16 |
Reserved |
|||||||||||||||
15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
Reserved |
master_on_hold RO 0x0 |
restart_det RO 0x0 |
gen_call RO 0x0 |
start_det RO 0x0 |
stop_det RO 0x0 |
activity RO 0x0 |
rx_done RO 0x0 |
tx_abrt RO 0x0 |
rd_req RO 0x0 |
tx_empty RO 0x0 |
tx_over RO 0x0 |
rx_full RO 0x0 |
rx_over RO 0x0 |
rx_under RO 0x0 |
ic_raw_intr_stat Fields
Bit | Name | Description | Access | Reset |
---|---|---|---|---|
13 | master_on_hold | Indicates whether master is holding the bus and TX FIFO is empty. Reset value: 0x0 |
RO | 0x0 |
12 | restart_det | Indicates whether a RESTART condition has occurred on the I2C interface when it is operating in Slave mode and the slave is being addressed. (Note:Following are exceptions where the Restart interrupt will not get generated. In the case of a Startbyte transfer, where the Restart comes before the Address field as per the I2C protocol defined format, the Slave is still not in the addressed mode and hence will not generate the RESTART_DET interrupt.) Reset value: 0x0 |
RO | 0x0 |
11 | gen_call | Set only when a General Call address is received and it is acknowledged. It stays set until it is cleared either by disabling the I2C or when the CPU reads bit 0 of the IC_CLR_GEN_CALL register. The I2C stores the received data in the Rx buffer. Reset value: 0x0 |
RO | 0x0 |
10 | start_det | Indicates whether a START or RESTART condition has occurred on the I2C interface regardless of whether the I2C is operating in slave or master mode. Reset value: 0x0 |
RO | 0x0 |
9 | stop_det | The behavior of the STOP_DET interrupt status differs based on the STOP_DET_IFADDRESSED selection in the IC_CON register When STOP_DET_IFADDRESSED =0 Indicates whether a STOP condition has occurred on the I2C interface regardless of whether the I2C module is operating in slave or master mode. In slave mode, a STOP_DET interrupt is generated irrespective of whether the slave is addressed or not. When STOP_DET_IFADDRESSED = 1 In Master Mode (MASTER_MODE = 1), indicates a STOP condition has occured on the I2C interface. In Slave Mode (MASTER_MODE = 0), a STOP_DET interrupt is generated only if the slave is addressed. NOTE: During a general call address, this slave does not issue a STOP_DET interrupt if STOP_DET_IFADDRESSED=1, even if the slave responds to the general call address by generating ACK. The STOP_DET interrupt is generated only when the transmitted address matches the slave address (SAR). Reset value: 0x0. |
RO | 0x0 |
8 | activity | This bit captures the I2C activity and stays set until it is cleared. There are four ways to clear it: - Disabling the I2C module - Reading the IC_CLR_ACTIVITY register - Reading the IC_CLR_INTR register - System reset Once this bit is set, it stays set unless one of the four methods is used to clear it. Even if the the I2C module is idle, this bit remains set until cleared, indicating that there was activity on the bus. Reset value: 0x0 |
RO | 0x0 |
7 | rx_done | When the I2C is acting as a slave-transmitter, this bit is set to 1 if the master does not acknowledge a transmitted byte. This occurs on the last byte of the transmission, indicating that the transmission is done. Reset value: 0x0 |
RO | 0x0 |
6 | tx_abrt | This bit indicates if the I2C, as an I2C transmitter, is unable to complete the intended actions on the contents of the transmit FIFO. This situation can occur both as an I2C master or an I2C slave, and is referred to as a 'transmit abort'. When this bit is set to 1, the IC_TX_ABRT_SOURCE register indicates the reason why the transmit abort takes places. NOTE: The I2C flushes/resets/empties the TX FIFO whenever this bit is set. The TX FIFO remains in this flushed state until the register IC_CLR_TX_ABRT is read. Once this read is performed, the TX FIFO is then ready to accept more data bytes from the APB interface. Reset value: 0x0 |
RO | 0x0 |
5 | rd_req | This bit is set to 1 when the I2C is acting as a slave and another I2C master is attempting to read data from it. The HPS I2C holds the I2C bus in a wait state (SCL=0) until this interrupt is serviced, which means that the slave has been addressed by a remote master that is asking for data to be transferred. The processor must respond to this interrupt and then write the requested data to the IC_DATA_CMD register. This bit is set to 0 just after the processor reads the IC_CLR_RD_REQ register. Reset value: 0x0 |
RO | 0x0 |
4 | tx_empty | The behavior of the TX_EMPTY interrupt status differs based on the TX_EMPTY_CTRL selection in the IC_CON register. When TX_EMPTY_CTRL = 0: This bit is set to 1 when the transmit buffer is at or below the threshold value set in the IC_TX_TL register. When TX_EMPTY_CTRL = 1: This bit is set to 1 when the transmit buffer is at or below the threshold value. set in the IC_TX_TL register and the transmission of the address/data from the internal shift register for the most recently popped command is completed. It is automatically cleared by hardware when the buffer level goes above the threshold. When IC_ENABLE[0] is set to 0, the TX FIFO is flushed and held in reset. There the TX FIFO looks like it has no data within it, so this bit is set to 1, provided there is activity in the master or slave state machines. When there is no longer any activity, then with ic_en=0, this bit is set to 0. Reset value: 0x0. |
RO | 0x0 |
3 | tx_over | Set during transmit if the transmit buffer is filled to its maximum TxFIFO buffer depth (64) and the processor attempts to issue another I2C command by writing to the IC_DATA_CMD register. When the module is disabled, this bit keeps its level until the master or slave state machines go into idle, and when ic_en goes to 0, this interrupt is cleared. Reset value: 0x0 |
RO | 0x0 |
2 | rx_full | Set when the receive buffer reaches or goes above the RX_TL threshold in the IC_RX_TL register. It is automatically cleared by hardware when buffer level goes below the threshold. If the module is disabled (IC_ENABLE[0]=0), the RX FIFO is flushed and held in reset; therefore the RX FIFO is not full. So this bit is cleared once the IC_ENABLE bit 0 is programmed with a 0, regardless of the activity that continues. Reset value: 0x0 |
RO | 0x0 |
1 | rx_over | Set if the receive buffer is completely filled to its maximum RxFIFO depth (64) and an additional byte is received from an external I2C device. The HPS I2C acknowledges this, but any data bytes received after the FIFO is full are lost. If the module is disabled (IC_ENABLE[0]=0), this bit keeps its level until the master or slave state machines go into idle, and when ic_en goes to 0, this interrupt is cleared. Reset value: 0x0 |
RO | 0x0 |
0 | rx_under | Set if the processor attempts to read the receive buffer when it is empty by reading from the IC_DATA_CMD register. If the module is disabled (IC_ENABLE[0]=0), this bit keeps its level until the master or slave state machines go into idle, and when ic_en goes to 0, this interrupt is cleared. Reset value: 0x0 |
RO | 0x0 |