The document reports on progress connecting a router to a terminal through a USB-serial connection. It was successful in transferring text data but commands needed to be executable. The solution was to use a shell to pipe input and output between the terminal and router. An autorun script was also created to automatically load the USB-serial modules and start the shell on router boot for a manual-to-automatic process.

1. 專題進度報告
Week 9
Terminal through USB-Serial
Success Version
Ray
1

2. Review
 usbserial & pl2303 module is work.
 It's ok to communicate with router through USB-
Serial line, text data was transferred to router.
 Need to solve
 Text data should be command, and can be execute
on router
 Result should be return to terminal through USB-
Serial
2

3. Review
 Manual control in telnet
wget http://192.168.1.2/pl2303.o
wget http://192.168.1.2/usbserial.o
拔出 USB
insmod usbserial.o
insmod pl2303.o debug=1
mknod /dev/ttyUSB0 c 188 0
chmod 666 /dev/ttyUSB
3

4. Modify
 usbserial & pl2303 already build-in, not need
download again.
 Use directly
 insmod usbserial
 insmod pl2303
4

5. Review
5

6. Solution
 Text data should be command, and can be execute
on router
✔ Use a shell to pipe, sh ↔ terminal (GtkTerm)
✔ sh::in ← terminal::out
✔ sh::out → terminal::in
✔ sh::err → terminal::in
✔ /bin/sh < /dev/ttyUSB0 > /dev/ttyUSB0 2>&1
6

7. Modify Manual to Auto
 USB-Serial is ready after router bootup.
 Create a autorun script when booting.
 Router ON
 Extract image
 Execute /linuxrc
 Execute initd
 Execute /usr/local/sbin/post-boot
7

8. /usr/local/sbin/post-boot
#!/bin/sh
insmod usbserial
insmod pl2303
mknod /dev/ttyUSB0 c 188 0
chmod 666 /dev/ttyUSB0
/bin/sh < /dev/ttyUSB0 > /dev/ttyUSB0 2>&1
8

9. Save post-boot to Flash
 flashfs save
 flashfs commit
 flashfs enable
 reboot
 NOT NEED TO REBUILD IMAGE
9

10. HostPC GtkTerm Config
 Port: /dev/ttyS0
 Speed: 9600
 Parity: None
 Bits: 8
 Stopbits: 1
 FlowControl: None
10

11. HostPC GtkTerm Config
11

12. HostPC GtkTerm
12

13. Next Step
 Figure out network interrupt
 Packet forward through iptables

13