Updates for TQM5200 modules:

[karo-tx-uboot.git] / doc / README.NetConsole

diff --git a/doc/README.NetConsole b/doc/README.NetConsole
index 8dc0d29197ec0cba86a86a55d64638e137f1d65e..cc35a0a8ffe1148c91914b75bd3725e5533d0a2b 100644 (file)
--- a/doc/README.NetConsole
+++ b/doc/README.NetConsole
@@ -6,11 +6,26 @@ serial and network input/output devices by adjusting the 'stdin' and
 set either of these variables to "nc". Input and output can be
 switched independently.
 
+We use an environment variable 'ncip' to set the IP address and the
+port of the destination. The format is <ip_addr>:<port>. If <port> is
+omitted, the value of 6666 is used. If the env var doesn't exist, the
+broadcast address and port 6666 are used. If it is set to an IP
+address of 0 (or 0.0.0.0) then no messages are sent to the network.
+
+For example, if your server IP is 192.168.1.1, you could use:
+
+       => setenv nc 'setenv stdout nc;setenv stdin nc'
+       => setenv ncip 192.168.1.1
+       => saveenv
+       => run nc
+
+
 On the host side, please use this script to access the console:
 
 +++++++++++++++++++++++++++++++++++++++++++
 #! /bin/bash
 
+[ $# = 1 ] || { echo "Usage: $0 target_ip" >&2 ; exit 1 ; }
 TARGET_IP=$1
 
 stty -icanon -echo intr ^T
@@ -19,6 +34,37 @@ nc -u ${TARGET_IP} 6666
 stty icanon echo intr ^C
 +++++++++++++++++++++++++++++++++++++++++++
 
+The script expects exactly one argument, which is interpreted as  the
+target IP address (or host name, assuming DNS is working). The script
+can be interrupted by pressing ^T (CTRL-T).
+
+It turns out that 'netcat' cannot be used to listen to broadcast
+packets. We developed our own tool 'ncb' (see tools directory) that
+listens to broadcast packets on a given port and dumps them to the
+standard output. use it as follows:
+
++++++++++++++++++++++++++++++++++++++++++++
+#! /bin/bash
+
+[ $# = 1 ] || { echo "Usage: $0 target_ip" >&2 ; exit 1 ; }
+TARGET_IP=$1
+
+stty icanon echo intr ^T
+./ncb &
+nc -u ${TARGET_IP} 6666
+stty icanon echo intr ^C
+kill 0
++++++++++++++++++++++++++++++++++++++++++++
+
+Again, this script takes exactly one argument, which is interpreted
+as the target IP address (or host name, assuming DNS is working). The
+script can be interrupted by pressing ^T (CTRL-T).
+
+The 'ncb' tool can be found in the tools directory; it will not be
+built by default so you will ither have to adjust the Makefile or
+build it manually.
+
+
 For Linux, the network-based console needs special configuration.
 Minimally, the host IP address needs to be specified. This can be
 done either via the kernel command line, or by passing parameters
@@ -66,3 +112,6 @@ To browse the Linux network console output, use the 'netcat' tool invoked
 as follows:
 
        nc -u -l -p 6666
+
+Note that unlike the U-Boot implementation the Linux netconsole is
+unidirectional, i. e. you have console output only in Linux.