Module segger::rtt

source ·
Expand description

Segger RTT implementation.

RTT is a protocol for sending debugging messages to a connected host. The embedded platform configures a portion of memory in a special way, and then the host uses a JTAG connection to read the messages out of the chip’s memory.

§Receiving RTT Messages

With the jlink tools, receiving RTT messages is a two step process. First, open a JTAG connection with a command like:

$ JLinkExe -device nrf52 -if swd -speed 1000 -autoconnect 1

Then, use the JLinkRTTClient tool in a different terminal to print the messages:

$ JLinkRTTClient

§Todo

  • Implement receive functionality.

§Usage

ⓘ
pub struct Platform {
    // Other fields omitted for clarity
    console: &'static capsules::console::Console<'static>,
}

In main():

ⓘ

let virtual_alarm_rtt = static_init!(
    VirtualMuxAlarm<'static, nrf5x::rtc::Rtc>,
    VirtualMuxAlarm::new(mux_alarm)
);
virtual_alarm_rtt.setup();

let rtt_memory = static_init!(
    capsules::segger_rtt::SeggerRttMemory,
    capsules::segger_rtt::SeggerRttMemory::new(b"Terminal\0",
        &mut capsules::segger_rtt::UP_BUFFER,
        b"Terminal\0",
        &mut capsules::segger_rtt::DOWN_BUFFER)
);

let rtt = static_init!(
    capsules::segger_rtt::SeggerRtt<VirtualMuxAlarm<'static, nrf5x::rtc::Rtc>>,
    capsules::segger_rtt::SeggerRtt::new(virtual_alarm_rtt, rtt_memory,
        &mut capsules::segger_rtt::UP_BUFFER,
        &mut capsules::segger_rtt::DOWN_BUFFER)
);
virtual_alarm_rtt.set_client(rtt);

let console = static_init!(
    capsules::console::Console<'static>,
    capsules::console::Console::new(
        rtt,
        &mut capsules::console::WRITE_BUF,
        &mut capsules::console::READ_BUF,
        board_kernel.create_grant(&grant_cap)
    )
);
kernel::hil::uart::UART::set_client(rtt, console);
console.initialize();

Structs§

  • SeggerRtt
  • SeggerRttBuffer
  • SeggerRttMemory
    This structure is defined by the segger RTT protocol. It must exist in memory in exactly this form so that the segger JTAG tool can find it in the chip’s memory and read and write messages to the appropriate buffers.

Constants§