Add a Serial port to the MIPS Linkstation - Revision history

Davy gravy: /* Attach Header to the Board */

Davy gravy — Tue, 16 Sep 2008 01:30:28 GMT

Attach Header to the Board

← Older revision		Revision as of 01:30, 16 September 2008
Line 28:		Line 28:


-	== Attach ~~Header~~ to the Board ==	+	== Attach Headers to the Board ==
		+
		+	* The console header needs to be attached to the J1 pad, the jumper head to J2.
		+	* Remove the preexisting solder from J1 and/or J2. Some boards have no solder in the holes. If they do, a solder wick or solder syringe are idea for this.
		+	* If you are using angled/90-degree-bend headers, attaching them to the back/outside of the circuit board is ideal.
		+	* Solder carefully and quickly to avoid board damage.
		+	* If you are using the back-of-the-board placement, labeling the pins 1-4 w/ a marker saves you time in when it comes to hooking up your adapter.

-	* The console header needs to be attached to the J1 pad
-	* Remove the preexisting solder from J1

Davy gravy: /* Prerequisites */

Davy gravy — Tue, 16 Sep 2008 01:21:48 GMT

Prerequisites

← Older revision		Revision as of 01:21, 16 September 2008
Line 17:		Line 17:
	* (1) 0.015", 1 oz solder		* (1) 0.015", 1 oz solder
	* (1) 0.1” series PCB header plug, 4-pin (for the serial port on J1) the 90-degree bend type is nice if you want to attach it on the back of the board		* (1) 0.1” series PCB header plug, 4-pin (for the serial port on J1) the 90-degree bend type is nice if you want to attach it on the back of the board
-	* (1) 0.1” series PCB header plug, 2-pin (for the enabling jumper) 90-degree also nice here, same as above	+	* (1) 0.1” series PCB header plug, 2-pin (for the enabling jumper on J2) 90-degree also nice here, same as above
		+	* (1) jumper for the header on J2 - the kind from an old IDE hdd is ideal
	* (1) Serial converter (or build your own - see [[Add a Serial port to the MIPS Linkstation#The_Serial_Converter \| step 4]])		* (1) Serial converter (or build your own - see [[Add a Serial port to the MIPS Linkstation#The_Serial_Converter \| step 4]])

Davy gravy: /* Prerequisites */

Davy gravy — Tue, 16 Sep 2008 01:19:48 GMT

Prerequisites

← Older revision		Revision as of 01:19, 16 September 2008
Line 16:		Line 16:
	* (1)Electronic-grade soldering iron (think really small)		* (1)Electronic-grade soldering iron (think really small)
	* (1) 0.015", 1 oz solder		* (1) 0.015", 1 oz solder
-	* (1) 0.1” series PCB header plug, 4-pin	+	* (1) 0.1” series PCB header plug, 4-pin (for the serial port on J1) the 90-degree bend type is nice if you want to attach it on the back of the board
		+	* (1) 0.1” series PCB header plug, 2-pin (for the enabling jumper) 90-degree also nice here, same as above
	* (1) Serial converter (or build your own - see [[Add a Serial port to the MIPS Linkstation#The_Serial_Converter \| step 4]])		* (1) Serial converter (or build your own - see [[Add a Serial port to the MIPS Linkstation#The_Serial_Converter \| step 4]])
-

	== Access the Board ==		== Access the Board ==

Davy gravy: /* Enabling the Serial Console */

Davy gravy — Tue, 16 Sep 2008 00:42:05 GMT

Enabling the Serial Console

← Older revision		Revision as of 00:42, 16 September 2008
Line 63:		Line 63:

	== Enabling the Serial Console ==		== Enabling the Serial Console ==
		+	===Hardware===

-	As the LS2 only has a single serial port which is used by the housekeeping microcontroller, it is necessary to enable the serial console. This is done by jumpering the pins of J2 and disabling the watchdog timer on startup (by pressing the red button and ~~powereing~~ it up). It is easiest to install J2 on the back of the board as it will be accessible by removing the cover and not the board from the chassis I used a red jumper so it can be easily located. Another option to removing the cover is to drill a 3/8" hole in the case directly above J2 and make a handle for your jumper from a piece of tape.	+	As the LS2 only has a single serial port which is used by the housekeeping microcontroller, it is necessary to enable the serial console. This is done by jumpering the pins of J2 and disabling the watchdog timer on startup (by pressing the red button and powering it up). It is easiest to install J2 on the back of the board as it will be accessible by removing the cover and not the board from the chassis I used a red jumper so it can be easily located. Another option to removing the cover is to drill a 3/8" hole in the case directly above J2 and make a handle for your jumper from a piece of tape.

	Note that the jumper doesn't change the hardware configuration but its state can be read by the CPU using GPIO8 ("0" jumper on, "1" jumper off). The original Linux kernel registers the serial console if the jumper is on.		Note that the jumper doesn't change the hardware configuration but its state can be read by the CPU using GPIO8 ("0" jumper on, "1" jumper off). The original Linux kernel registers the serial console if the jumper is on.
		+
		+	===Software===
		+	Make sure that the distro you are booting actually has a some means to offer you a login window through the serial connection. A standard way of doing this would be to make sure that /etc/inittab has some line, perhaps at the end, like this:
		+	T0:23:respawn:/sbin/getty -L ttyS0 57600
		+
		+	Also remember to switch output to the serial port with a bootargs statement such as :
		+	setenv bootargs console=ttyS0 root=/dev/hda1 rw
		+	instead of the netconsole= option.

	== Using the Serial Console ==		== Using the Serial Console ==

Ramuk: /* The Serial Converter */

Ramuk — Sat, 18 Aug 2007 13:41:15 GMT

The Serial Converter

← Older revision		Revision as of 13:41, 18 August 2007
Line 60:		Line 60:

	== The Serial Converter ==		== The Serial Converter ==
-	~~===Buy One===~~	+	{{Level Shifter}}
-	The serial port signals from the processor are only 3.3V. For proper RS-232 12V signaling, an RS-232 level shifter needs to be added. These are very common in PDA serial cables also, but can be purchased: See [[Serial_port#Buy_a_TTL.2FRS232_or_TTL.2FUSB_interface \| Serial port: Buy a TTL/RS232 or TTL/USB interface]]	+
-		+
-	~~===Build One===~~	+
-	~~[[Building a Custom Serial Interface]]~~	+

	== Enabling the Serial Console ==		== Enabling the Serial Console ==

Ramuk: /* The Serial Converter */

Ramuk — Sat, 18 Aug 2007 04:33:42 GMT

The Serial Converter

← Older revision		Revision as of 04:33, 18 August 2007
Line 60:		Line 60:

	== The Serial Converter ==		== The Serial Converter ==
-
	===Buy One===		===Buy One===
-	The serial port signals from the processor are only 3.3V. For proper RS-232 12V signaling, an RS-232 level shifter needs to be added. These are very common in PDA serial cables also, but can be purchased ~~from~~	+	The serial port signals from the processor are only 3.3V. For proper RS-232 12V signaling, an RS-232 level shifter needs to be added. These are very common in PDA serial cables also, but can be purchased: See [[Serial_port#Buy_a_TTL.2FRS232_or_TTL.2FUSB_interface \| Serial port: Buy a TTL/RS232 or TTL/USB interface]]
-	[~~http://www~~.~~superdroidrobots~~.~~com~~/~~shop/item.asp?itemid=335&catid=41 SuperDroid Robots] (#MCU-026-172)~~ or ~~[http://www.compsys1.com/workbench~~/ ~~CompSys~~] ~~(#A232DBH3v).~~	+

	===Build One===		===Build One===
-	~~: As an alternative you can make the level shifter cable yourself:~~	+	[[Building a Custom Serial Interface]]
-	:'''Warning: The following image depicts 0.1mF (m = milli) capacitors, while in reality 0.1µF (µ = micro), alias 100nF (n = nano) capacitors are needed for the original MAX3232! The list of parts is correct.'''	+
-		+
-	[[~~Image:Shifter.jpg\|400px]]~~	+
-	~~: Components can be found at e.g. [http://www.digikey.com Digikey]~~	+
-		+
-	* If you want to build your own serial converter, you will need the following parts:	+
-	* (5) 0.1 µF tantalum capacitors	+
-	* (1) MAX3232CPE IC (Maxim), 3V type, 16 pin DIL	+
-	* (1) RS232 male socket	+
-	* (1) Some perf board (about 1" x 1")	+
-	* (1) Wire	+
-		+
-		+
-	~~You can etch~~ a ~~circuit board which makes building the interface and installing the interface really easy. Instructions are [http://www.kurobox.com/mwiki/index.php/Building_a_Custom_Serial_Interface Here~~].	+
-		+
-	~~This should be attached as close as possible to the board. The signals are very weak and wires as short as 2" (5 cm) have been reported to cause data loss across the serial port.~~	+
-		+
-		+
-	* [http://en.wikibooks.org/wiki/Serial_Programming:MAX232_Driver_Receiver Some details about the MAX232 family]	+
-	* [http://pdfserv.maxim-ic.com/en/ds/MAX3222-MAX3241.pdf Original manufacturer's MAX RS32xx Family Datasheet]	+

	== Enabling the Serial Console ==		== Enabling the Serial Console ==

Linuxnotincluded: /* Enabling the Serial Console */

Linuxnotincluded — Wed, 18 Jul 2007 00:42:33 GMT

Enabling the Serial Console

← Older revision		Revision as of 00:42, 18 July 2007
Line 91:		Line 91:

	As the LS2 only has a single serial port which is used by the housekeeping microcontroller, it is necessary to enable the serial console. This is done by jumpering the pins of J2 and disabling the watchdog timer on startup (by pressing the red button and powereing it up). It is easiest to install J2 on the back of the board as it will be accessible by removing the cover and not the board from the chassis I used a red jumper so it can be easily located. Another option to removing the cover is to drill a 3/8" hole in the case directly above J2 and make a handle for your jumper from a piece of tape.		As the LS2 only has a single serial port which is used by the housekeeping microcontroller, it is necessary to enable the serial console. This is done by jumpering the pins of J2 and disabling the watchdog timer on startup (by pressing the red button and powereing it up). It is easiest to install J2 on the back of the board as it will be accessible by removing the cover and not the board from the chassis I used a red jumper so it can be easily located. Another option to removing the cover is to drill a 3/8" hole in the case directly above J2 and make a handle for your jumper from a piece of tape.
		+
		+	Note that the jumper doesn't change the hardware configuration but its state can be read by the CPU using GPIO8 ("0" jumper on, "1" jumper off). The original Linux kernel registers the serial console if the jumper is on.

	== Using the Serial Console ==		== Using the Serial Console ==

Linuxnotincluded: /* Enable Full Serial Tx/Rx */

Linuxnotincluded — Wed, 18 Jul 2007 00:29:23 GMT

Enable Full Serial Tx/Rx

← Older revision		Revision as of 00:29, 18 July 2007
Line 55:		Line 55:
	== Enable Full Serial Tx/Rx ==		== Enable Full Serial Tx/Rx ==

-	To enable write support across the serial port, simply bridge R186.	+	<strike>To enable write support across the serial port, simply bridge R186.</strike>

		+	Install R186 using a 330 ohm resistor. Simply bridging R186 will stop the microcontroller from sending data to the CPU.

	== The Serial Converter ==		== The Serial Converter ==

131.156.18.53: /* Using the Serial Console */

131.156.18.53 — Mon, 05 Mar 2007 23:46:38 GMT

Using the Serial Console

← Older revision		Revision as of 23:46, 5 March 2007
Line 97:		Line 97:
	;Windows:You may access the serial console using Windows HyperTerminal (included with Windows) or [http://hp.vector.co.jp/authors/VA002416/teraterm.html TeraTerm Pro] terminal emulator.		;Windows:You may access the serial console using Windows HyperTerminal (included with Windows) or [http://hp.vector.co.jp/authors/VA002416/teraterm.html TeraTerm Pro] terminal emulator.
	;classic Unix:If you have a classic Unix you should either have '''tip'''(1) or '''cu'''(1) (or both). They are suitable to set up a serial connection. Linux typically doesn't have these.		;classic Unix:If you have a classic Unix you should either have '''tip'''(1) or '''cu'''(1) (or both). They are suitable to set up a serial connection. Linux typically doesn't have these.
-	;Linux:If you are on Linux, consider the trusted and tried [http://alioth.debian.org/projects/minicom/ miniterm] terminal emulator.	+	;Linux:If you are on Linux, consider the trusted and tried [http://alioth.debian.org/projects/minicom/ miniterm] terminal emulator. 'minicom' also works nicely.
	;Terminal:If you are the proud owner of a real oldschool terminal, this is your chance to make use of the old dust catcher :-)		;Terminal:If you are the proud owner of a real oldschool terminal, this is your chance to make use of the old dust catcher :-)

212.117.81.29: /* Build One */

212.117.81.29 — Tue, 31 Oct 2006 15:14:07 GMT

Build One

← Older revision		Revision as of 15:14, 31 October 2006
Line 66:		Line 66:
	===Build One===		===Build One===
	: As an alternative you can make the level shifter cable yourself:		: As an alternative you can make the level shifter cable yourself:
-	~~<red>~~Warning: The following image depicts 0.1mF (m = milli) capacitors, while in reality 0.1µF (µ = micro) capacitors are needed for the original MAX3232! The list of parts is correct.~~</red>~~	+	:'''Warning: The following image depicts 0.1mF (m = milli) capacitors, while in reality 0.1µF (µ = micro), alias 100nF (n = nano) capacitors are needed for the original MAX3232! The list of parts is correct.'''
		+
	[[Image:Shifter.jpg\|400px]]		[[Image:Shifter.jpg\|400px]]
	: Components can be found at e.g. [http://www.digikey.com Digikey]		: Components can be found at e.g. [http://www.digikey.com Digikey]