Hi Josef,

is it possible to use two UARTs at the same time from within one app? We had a look at the example script and application repos/os/run/uart.run and repos/os/src/test/uart and tried several things, including:

• adding two lines in the config for the same process but with different UARTs: <policy label="test-uart1" uart="1"/> <policy label="test-uart1" uart="2"/>

• comma-separating UARTs (uart="1,2")

• adding a second uart-attribute (uart="1" uart="2")

• and many more.

• In the application, we simply added a second instance of

Uart::Connection and accessed it in the same way as the first. (The Uart::Connection doesn't seem to offer any other constructor than the default one, in which one could specify which UART to access.)

but all of those attemptes either led to a build error or made the output appear on only one UART. Is there any way to access two UARTs in one application or would we need a separate process for each one?

when using multiple connections, each connection should be equipped with a specific label to enable the server (the UART driver) to distinguish them. Unfortunately, the constructor of 'Uart_connection' lacks a parameter for an optional 'label' argument. To accommodate your scenario, you would need to add such an argument similar to how it is done in 'Terminal::Connection'. Btw, unless you really need the specific baud-rate settings of the 'Uart' session, you may just use a 'Terminal::Connection' instead. This would work because the UART driver provides both a "Terminal" service and an "Uart" service.

Once you have passed a different label to each connection, you may add a dedicated <policy> node for each label to the driver's configuration. For example, if your connections have the labels "adam" and "eve", the policy would look like this (the "->" is the separator of the label elements):

<policy label="test-uart1 -> adam" uart="1"/> <policy label="test-uart1 -> eve" uart="2"/>

In case you decide to extend the 'Uart::Connection' constructor with a 'label' argument, please tell us. So we can do same for the mainline of Genode.

Cheers Norman