SPRUJ28E November 2021 – September 2024 AM68 , AM68A , TDA4AL-Q1 , TDA4VE-Q1 , TDA4VL-Q1
A system test mode is available for multicontroller I2C module testing. This mode is enabled by setting the I2C_SYSTEST[15] ST_EN bit to 1. When this bit is cleared to 0, the I2C controller is configured in normal operation mode.
In system test mode, the I2C_SYSTEST[13-12] TMODE bit field selects the type of test. Table 12-22 lists the tests available for the multicontroller HS I2C controllers.
I2C_SYSTEST[13-12] TMODE | Test | Description |
---|---|---|
00 | Functional mode | Normal operation mode |
01 | Reserved (not used) | |
10 | Test of SCL serial clock line | The SCL line is driven with a permanent clock as if controlled with the parameters set in the I2C_PSC, I2C_SCLL, and I2C_SCLH registers. |
11 | Loop-back mode + SCL/SDA I/O | In controller transmit mode only, data transmitted out of the I2C_DATA register (write action) is received in the same I2C_DATA register through an internal path through the FIFO buffers. The interrupt request is normally generated if it is enabled. Moreover, the SCL and SDA are controlled with the I2C_SYSTEST[3-0] bits. |
When the I2C_SYSTEST[13-12] TMODE bit field is set to 11, the I2C controller must be configured in I2C F/S (I2C_CON[13-12] OPMODE set to 00) or I2C HS mode (I2C_CON[13-12] OPMODE set to 01).
In normal operation mode (the I2C_SYSTEST[15] ST_EN bit cleared to 0), the I2C_SYSTEST[3-0] bits that control the SCL, SDA lines in system test mode are read-only bits.
In system test mode (the I2C_SYSTEST[15] ST_EN bit set to 1), the I2C_IRQSTATUS_RAW[4] XRDY, I2C_IRQSTATUS_RAW[3] RRDY, I2C_IRQSTATUS_RAW[10] XUDF, I2C_IRQSTATUS_RAW[11] ROVR, I2C_IRQSTATUS_RAW[2] ARDY and I2C_IRQSTATUS_RAW[1] NACK status bits can be set to 1 when the I2C_SYSTEST[11] SSB bit is set to 1. Clearing the I2C_SYSTEST[11] SSB bit to 0 does not clear the I2C_IRQSTATUS_RAW bits to 0. The I2C_IRQSTATUS_RAW bit field can be cleared to 0 only by writing 1 in the corresponding bits.