PRU on Beaglebone AI 64

General Discussion
1

I saw this in TI’s document on the PRU, does it mean that TI is removing it from future releases?

The J721E hardware includes the PRU peripheral, that has been deprecated by TI and is not
supported in TI software. This document highlights its features for posterity, and to enable its use in scenarios that do not require or expect TI support.

There are tons of UART on the device and it doesn’t look like any beside UART0, UART2 are brought out beside the one that shares pins with a CAN port.
Since UART0 is the debug port I didn’t want to use it.

I need two UARTs, one for LIN and one for J1587

How can I simulate a uart with the PRU on this board? I can’t see any documentation beside that of the Beaglebone black or Beagleboard X15

Michel

2

If memory serves me correctly there are at least 5 uarts (besides debug uarts) available on the AI64, of course that will depend on what else you are using.

3

I was looking at the schematic and didn’t find many,
I downloaded the datasheet for the device and found that there is a typo in the schematic
On P8-28 and P8-29 it is UART8 and not UART0
So the UART available on the connectors are UART1, UART2, UART3, UART4, UART5, UART6 and UART8
As for the CAN ports only MCAN1, MCAN3, MCAN12 and MCAN13 are not brought to the connectors which means that you can have as many as 10 CAN ports.
The most I’ve ever used was 5 CAN. Here with 10 CAN ports I can do a lot of tests for 5 CAN ports with the extra 5 CAN

What is puzzling is debug is on WKUP_UART0 and the click has MCU_UART0
On P9 there is also a UART0, all 3 on different pins on the processor

Is that the same UART?

Michel

4

Thats not a typo, just confusing it refers to the PRU UART0 pins and not UART0. But yes UART8 is also on those pins. The schematic pin labels does not list all the possible functions for a pin. It would make the labels much too long.

I put together a spreadsheet for the BBAI-64 pin muxing - BBAI-64 pin mux spreadsheet which might be of use.

wkup_uart0 and mcu_uart0 are different. however uart0 on the headers I think is the same as mcu_uart0, justed muxed to different pins.

1 Like