UARTs from GPIO headers

[maks.dav]

I need 4 UARTs, to use board as controller for home automatization: 1 - ZeegBee, 1 - GSM, 1 - RS485, 1 - M-bus. But in documentation, there are only 2 gpio uarts enabled for user. I wouldn't like to use external usb converters, this interfaces should be located on my expansion board, connected to the rock64 by GPIOs. Is there any solutions to solve my problem?

[tllim]

I need 4 UARTs, to use board as controller for home automatization: 1 - ZeegBee, 1 - GSM, 1 - RS485, 1 - M-bus. But in documentation, there are only 2 gpio uarts enabled for user. I wouldn't like to use external usb converters, this interfaces should be located on my expansion board, connected to the rock64 by GPIOs. Is there any solutions to solve my problem?

no solution for 4 UARTs from GPIO

[martinayotte]

There is only 2 UARTs on header, UART2 and UART1 if DT is changed accordingly !
But you can add a SC16IS750 on SPI bus, that will provide 2 additional UARTs ...

[maks.dav]

There is only 2 UARTs on header, UART2 and UART1 if DT is changed accordingly !
But you can add a SC16IS750 on SPI bus, that will provide 2 additional UARTs ...

Thank you so much for answer, it's a good idea!
May be you know any normal tutorial, how to add and configure chips like SC16IS750 in system and add new serial ports to /dev?