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10 years ago

UART1 (/dev/ttyS1) on DE0-nano-SoC does not work

Hi! This is another question from a newbie.

HPS in DE0-nano-SoC has 2 UARTs. First of them (UART0) is used for console (ttyS0) via USB.

I want to use second UART (UART1) for data transfer from Linux (Debian wheezy armhf).

I used Linux 4.3 By Altera https://github.com/altera-opensource/linux-socfpga/releases/tag/v4.3

(https://github.com/altera-opensource/linux-socfpga/releases/tag/v4.3)

My first test was to open /dev/ttyS0 via ssh. (stty -F /dev/ttyS0)

Device was successfully opened and keystrokes successfully transmitted to the serial terminal

But I was unable to open /dev/ttyS1 (stty -F /dev/ttyS1) with error

stty: /dev/ttyS1: input/output error

In /proc/tty/driver/serial I have:


serinfo:1.0 driver revision:
0: uart:16550A mmio:0xFFC02000 irq:35 tx:10401 rx:724 RTS|DTR
1: uart:unknown mmio:0xFFC03000 irq:36

Output of Linux starting:


Serial: 8250/16550 driver, 2 ports, IRQ sharing disabled
 ffc02000.serial0: ttyS0 at MMIO 0xffc02000 (irq = 35, base_baud = 6250000) is a 16550A

but no information about ttyS1.

Its seems that ttyS1 is not connected to UART1.

How can I activate /dev/ttyS1?

[UPDATE]

In precompiled SD-card image from terrasic http://www.terasic.com/downloads/cd-rom/de0-nano-soc/linux_bsp/de0_nano_soc_linux_console_3.13.zip

there is same problem

But in image from rocketboards http://releases.rocketboards.org/release/2015.10/atlas/atlas_sdcard_v1.1.img.tgz

UART1 works well!

Thanks. Sorry for my english
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