PINE64

Full Version: Need to access 4 RockPro64 UARTs via Pins.
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Need WiFi, Bluetooth, and UARTs. Don't need GigE.
1. I looked at Google: rk3399.dtsi, and found addresses for uart0 - uart4
2. Used enable_dtoverlay to enable ports
  enable_dtoverlay uart0 'serial@ff180000' okay
  enable_dtoverlay uart1 'serial@ff190000' okay         # Disabled ethernet for this.
#enable_dtoverlay uart2 'serial@ff1a0000' okay         # Already active The only on that works,
  enable_dtoverlay uart3 'serial@ff1b0000' okay
  enable_dtoverlay uart4 'serial@ff370000' okay

Oscilloscope with the following script only show output for ttyS2. (PI bus pins 8,10)
while : ; do echo xx > /dev/ttyS0; echo xx > /dev/ttyS1; echo xx > /dev/ttyS2; echo xx > /dev/ttyS3 ;echo xx > /dev/ttyS4; echo -n . ; sleep 1; done

Looked at the Pine A64 pin assignments,
    0)  uart0  /dev/ttyS0   console
    2)  uart2   /dev/ttyS2   PI bus            pin(8) and pin(10)
    3)  uart3   /dev/ttyS3   Euler bus      pin(24) and pin(23)
    4)  uart4   /dev/ttyS4   Euler bus      pin(19) and  pin(21)
but RockPro64 has no Euler bus. Are all RockPro64 UART pins accessible?
(04-09-2019, 09:12 PM)rhex Wrote: [ -> ]Are all RockPro64 UART pins accessible?

No ! The UART1 and UART3 pins are used as ethernet pins.
The UART0 is available on WiFi headers for Bluetooth,
The UART2 is on the main header, as well as UART4 shared as SPI pins.

The schematic is useful to figure out such things ...

BTW, if you need more UARTs, it is better to attach some SC16IS752 to SPI port, it is a Dual Uart chip.
You also can check out PCIe to UART break up board, https://www.amazon.com/StarTech-com-RS23...004WKTBHW/

However, you may need to port the PCIe driver yourself and such card sometimes selling quite cheap at eBay. Some card also extend to 8 UART ports.