A20 GPIO List 2 Debian

[BibiBug]

Hi all, i read the user manual of the A20 SOM, and i dont find any information about serial ports.
i want to use UART6 (tx/rx) they are at pins 28,27 gpio2. My question is "which ttsy i must use?"
how can i find the relation between the hardware and linux software?
Regards

[Gerrit]

Code Select Expand

$ dmesg |grep uart
[    0.635489] [uart]: used uart info.: 0x11
[    0.640172] [uart]: serial probe 0 irq 33 mapbase 0x01c28000
[    0.666373] sunxi-uart.0: ttyS0 at MMIO 0x1c28000 (irq = 33) is a U6_16550A
[    1.399169] [uart]: serial probe 4 irq 49 mapbase 0x01c29000
[    1.430998] sunxi-uart.4: ttyS1 at MMIO 0x1c29000 (irq = 49) is a U6_16550

[BibiBug]

Thank you Gerrit for your answer.

i have this
root@a20-olimex:~#
root@a20-olimex:~# dmesg | grep uart
[    0.633432] [uart]: used uart info.: 0xf9
[    0.638168] [uart]: serial probe 0 irq 33 mapbase 0x01c28000
[    0.664400] sunxi-uart.0: ttyS0 at MMIO 0x1c28000 (irq = 33) is a U6_16550A
[    1.403525] [uart]: serial probe 3 irq 36 mapbase 0x01c28c00
[    1.435352] sunxi-uart.3: ttyS1 at MMIO 0x1c28c00 (irq = 36) is a U6_16550A
[    1.447157] [uart]: serial probe 4 irq 49 mapbase 0x01c29000
[    1.478950] sunxi-uart.4: ttyS2 at MMIO 0x1c29000 (irq = 49) is a U6_16550A
[    1.490736] [uart]: serial probe 5 irq 50 mapbase 0x01c29400
[    1.522527] sunxi-uart.5: ttyS3 at MMIO 0x1c29400 (irq = 50) is a U6_16550A
[    1.534310] [uart]: serial probe 6 irq 51 mapbase 0x01c29800
[    1.566095] sunxi-uart.6: ttyS4 at MMIO 0x1c29800 (irq = 51) is a U6_16550A
[    1.577874] [uart]: serial probe 7 irq 52 mapbase 0x01c29c00
[    1.609647] sunxi-uart.7: ttyS5 at MMIO 0x1c29c00 (irq = 52) is a U6_16550A
root@a20-olimex:~#

So to use the UART 6, i must use the ttyS4.

Have a nice day.