[FAQ] AM625 / AM623 / AM620-Q1 / AM62Ax / AM62Px / AM62D-Q1 / AM62L Design Recommendations / Custom board hardware design - Queries related to MCASP

Hi Board Designers, 

Multichannel Audio Serial Port (MCASP)
The MCASP functions as a general-purpose audio serial port and are optimized to the requirements of various audio applications. The MCASP module can operate in both transmit and receive modes. The MCASP is useful for
time-division multiplexed (TDM) stream, Inter-IC Sound (I2S) protocols reception and transmission as well as for an inter-component digital audio interface transmission (DIT). The MCASP has the flexibility to gluelessly connect to a Sony/Philips digital interface (S/PDIF) transmit physical layer component.
Multichannel Serial Peripheral Interface (MCSPI)
The MCSPI module is a multichannel transmit/receive, controller/peripheral synchronous serial bus.

McASP Design Guide - Tips, Tricks, and Practical Examples
https://www.ti.com/lit/an/sprack0/sprack0.pdf

Data pins for McASP instances

(25) AM62D-Q1: McASP Audio Ports - Processors forum - Processors - TI E2E support forums

3x Multichannel Audio Serial Ports (McASP)

– Transmit and Receive Clocks up to 50MHz

– Up to 4/6/16 Serial Data Pins across 3x McASP with Independent TX and RX Clocks

https://www.ti.com/lit/ds/symlink/am62d-q1.pdf

Regards,

Sreenivasa

Hi Board Designers, 

Refer below FAQs:

e2e.ti.com/.../am620-q1-mcasp-interface

Please refer below inputs i received from the expert.

The proposed setup looks ok. Since not details on the communication format have been provide, just some comments on the configuration.

MCASP0 * Bluetooth and Tuner must be running with the same format (TDM/I2S/etc) and word size setup and are synchronized with the bit clock and frame Sync
MCASP2 * Codec and amplifier must be running with the same format (TDM/I2S/etc) and word size setup and are synchronized with the bit clock and frame Sync

Two devices can be connected to McASP. It is recommended to follow good layout practices when routing the bit clock. Use the IBIS model to check signal integrity.
The required configuration is valid. Please use the SysConfig tool to ensure correct peripheral/IOSet configuration.

Synchronous Transmit and Receive Operations -
When the MCASP_ACLKXCTL[6] ASYNC bit is written to 0b0, the transmit and receive sections operate
synchronously to the transmit section clock and transmit frame sync signals.
Though Rx section may have a different data format, it has to be configured to have the same slot size than
the transmit section one.

e2e.ti.com/.../66ak2g12-soc-to-codec-connection-and-design-verification
Each McASP serializer can be set as either Rx, Tx, or none. You can see an example within k3-j721e-common-proc-board.dts where mcasp10 has 4 serializers set as Tx and 3 serializers set as Rx.
e2e.ti.com/.../5616314
e2e.ti.com/.../5746365
e2e.ti.com/.../5743314
https://e2e.ti.com/support/processors-group/processors/f/processors-forum/1469999/audio-am62d-evm-how-to-get-a-quick-start-with-am62d/5644096?tisearch=e2e-sitesearch&keymatch=MCASP#5644096

Regards,

Sreenivasa

Hi Board Designers, 

Inputs related to series resistor recommendation on the clock output

I have customer designing the custom board using AM62D  McASP bit clock output and did not connect the recommended 22R near to the SOC clock output pin (source).  Customer is checking on the effect of not adding the 22R? 

Device Expert input:

Not including a series termination resistor near the source end of a signal that loops back the clock is very likely to be problematic.  The source end of a signal will have a mid-supply step that is likely to generate glitches on every transition of the internal clock that gets looped back from the pin.  The series resistor allows you to shift the voltage of the step away from the switching threshold of the input buffer.  I would never design a board without the series resistor.

Regards,

Sreenivasa

Hi Board Designers,

FYI

Application Note AM62x Audio System Design Guide

AM62x Audio Design Guide

Application Note AM275x Audio System Design Guide

McASP Design Guide

Regards,

Sreenivasa