SPRUIL1D May 2019 – December 2024 DRA829J , DRA829J-Q1 , DRA829V , DRA829V-Q1 , TDA4VM , TDA4VM-Q1
The procedure in Table 12-510 initializes a MCASP serializer n receiver(s) to operate in TDM-mode (the only mode supported by MCASP receivers) after a power-on reset (POR). This is used for I2S (2-slot TDM) and other TDM-based audio protocols reception.
Before performing MCASP global initialization, If external clock ACLKR is used, it must be running already for proper synchronization of the MCASP_GBLCTL register.
The MCASP receivers support only TDM-frames (including 384-TDM frames) reception. DIT-frames reception (this is, S/PDIF stream) can be implemented indirectly via an external DIR-chip converter with DIT-input and TDM (I2S)-compatible output connected to device MCASP receiver input (TDM-only compatible).
| Step | Register/Bit Field/Programming Model | Value |
|---|---|---|
| 1. Apply software reset to different MCASP receive components. | MCASP_GBLCTL[4-0] | 0x00 |
| 2. Poll the bits to ensure the active reset value (0x00) is successfully latched into the register. | MCASP_GBLCTL[4-0] | =0x00 |
| 3. Configure the local power management. | MCASP_PWRIDLESYSCONFIG[1-0] IDLE_MODE | 0x1 |
| 4. Configure the receive format unit. | See Section 12.5.2.5.1.2.2.1. | |
| 5. Configure the receive frame sync generator. | See Section 12.5.2.5.1.2.2.2. | |
| 6. Configure the receive clock generator. | See Section 12.5.2.5.1.2.2.3. | |
| 7. Program all bits - RTDMSk (where k = 0 to 31) according to the time slot characteristics desired (positions of active versus inactive slots within a frame). | MCASP_RTDM[k] RTDMSk , where k = 0 to 31 | 0x- |
| 8. Configure the desired n-th serializer for receive mode operation.(4) | MCASP_SRCTLn [1-0] SRMOD; n = 0 to 15 | 0x2 |
| 9. Configure the MCASP pins functionality. | See Section 12.5.2.5.1.2.2.4. | |
| 10. Optional: Configure a MCASP Rx channel for a loopback operation (TDM mode only) in MCASP_DLBCTL [31-0]. | See Section 12.5.2.4.15.1, Loopback Mode Configurations. | 0x-(5) |
| 11. Release from reset state the divider that outputs the AHCLKR clock.(1) See also(2). | MCASP_GBLCTL[1] RHCLKRST | 0x1 |
| 12. Poll the bit to ensure that it is successfully latched in the register. See also(2). | MCASP_GBLCTL[1] RHCLKRST | =0x1 |
| 13. Release from reset state the divider that outputs the ACLKR clock. (1) See also(3). | MCASP_GBLCTL[0] RCLKRST | 0x1 |
| 14. Poll the bit to ensure that it is successfully latched in the register. See also(3). | MCASP_GBLCTL[0] RCLKRST | =0x1 |