Add a Serial port to the PowerPC Linkstation
The console is the text output device for system administration messages. These messages come from the kernel, from the init system and from the system logger. On modern small computers the console is usually the computer's attached monitor and keyboard. The LinkStation, however, doesn't have monitor output; instead, it uses a serial connection for console output. Not only does the serial console provide valuable debugging output, it also allows root access!
- %block bgcolor=#99FF99 border%(1) Electronic-grade soldering iron
- (1) 0.015", 1 oz silver-bearing solder
- (1) Desolder braid, solder sucker, or Servisol Soldamop
- (1) 0.1” series PCB header plug, 4-way
- (1) Serial converter (or build your own - see Stage 4)
- (1) Tweezers
- (1) Anti-static wrist strap%%
Stage 1 - Access the Board
- Disassemble the LinkStation.
- Remove the main circuit board by removing the 4 mounting screws:
- Place the circuit board on a static-free work area:
Stage 2 - Attach Header to the Board
- The console header needs to be attached to the J1 pad:
- Remove the preexisting solder from J1:
- Solder the PCB header to J1 so that the pinouts face towards the IDE header:
- The pinout for J1: \\
- 1: Transmit (TX) \\
- 2: Receive (RX) \\
- 3: Power (3.3V) \\
- 4: Ground (GND)
Stage 3 - Enable Full Serial Tx/Rx
Desoldering Tip | To desolder an SMD resistor you can apply the following trick: Take a short piece of blank wire. Bend one end into a small U-shape using some small pliers. The U-shape should be as such that you can touch the sides of both ends of the resistor at the same time. The width of the U should basically be the length of the resistor. Wrap the other end of the wire around the tip of your soldering iron - while it is still cold. You now have a small U-shaped tool to remove the resistor. Heat up the iron. When the wire is hot enough, heat up the solder at both ends of the resistor and gently pull the resistor away from the pads with the U-shaped tip. Be careful, the resistor likes to end up on the floor.:)
- This stage may be skipped if you only want 1-way console output.
- Remove the 10K Ohm resistor from R75. Do not apply heat for too long or you will damage the 10K Ohm resistor:\\
- Solder the 10K Ohm resistor to R76:\\
Stage 4 - The Serial Converter
- You can purchase a preassembled serial converter (recommended) from [| SuperDroid Robots] (#MCU-026-172) or [| CompSys] (#A232DBH3v).
- If you want to build your own serial converter, you will need the following parts: \\
- (5) 0.1 uF resin dipped capacitors (Monroes), 16V \\
- (1) MAX3232CPE IC (Maxim), 3V type, 16 pin DIL \\
- (1) Right angled RS232 male socket \\
- (1) 10 element stripboard \\
- (1) 16 pin chip mount \\
- (1) Wire
- Then follow [| this diagram].
Stage 5 - Cleaning Up
- TO BE COMPLETED
Stage 6 - Using the Serial Console
- You may access the serial console using Windows HyperTerminal (included with Windows) or [| TeraTerm Pro].
- The serial port settings are as follows: \\
- Baud rate - 57600bps \\
- Data - 8 bit \\
- Parity - none \\
- Stop - 1 bit \\
- Flow control - none