NSLU2-Linux
view · edit · print · history

Info.PinoutOfInternalSerialPort History

Hide minor edits - Show changes to markup

May 24, 2008, at 05:24 PM by Pete --
Changed line 26 from:
RXDRight side of R128
to:
RXDRight side of R128. The resistor itself may not be present, but the pad is available to solder onto.
Added line 31:

A useful connection (eg, for data logging) using just RXD above and a suitable ground. I soldered wires to R128 and the shield of the existing ethernet port, and am now satisfactorily receiving data from my electricity-usage monitoring device.

August 11, 2005, at 01:10 AM by johnnywhoo_DeleteThis_AT_gmx_net -- RxD2+open-ended cable = brick (seemingly)
Added lines 22-23:

NOTE: If a longer open-ended cable is connected to RxD? your NSLU maybe won't boot! Check, that RxD? gets a proper signal at least at boot-time (every time, for example, a gps-receiver isn't connected to the soldered-on RxD2?-cable, it hangs somewhere during redboot-init. This was at least observed with two different NSLU2 boxes).

June 12, 2005, at 07:36 AM by tman --
Changed lines 10-13 from:

Pin 1 is the left-hand pin.

NB: In the photo above, a set of header pins has been attached to J2. As sold, J2 consists only of a series of solder pads.

to:

Pin 1 is the left-hand pin and marked on the NSLU2 PCB.

NB: In the photo above, a set of header pins has been attached to J2. As sold, J2 consists only of a series of solder filled holes in the PCB. If you wish to put a header on then you must remove the solder first.

Added lines 20-21:

There is a second serial port on the NSLU2 but only receive and CTS are connected. It is not possible to connect to the transmit line. The connection points are on the back of the NSLU2 PCB.

May 13, 2005, at 06:34 PM by kivper --
Changed lines 14-15 from:

By default, both Redboot and the Linux kernel use 115200,8,N,1 settings.

to:

By default, both RedBoot and the Linux kernel use 115200,8,N,1 settings.

November 20, 2004, at 02:50 AM by tman --
Changed lines 24-25 from:
TXDLeft side of R142
CTSNC
to:
TXDNC
CTSLeft side of R142
October 10, 2004, at 02:11 AM by tman --
Deleted lines 15-18:

Set DTR drop time to 0, and "modem has DCD line" to no, unless you know that your serial adapter ties DCD to DTR.

Make sure that your terminal program does not send a modem init string and that you have set it to software flow control, not hardware.

October 10, 2004, at 02:11 AM by tman --
Changed lines 1-14 from:

Here's the pinout for the "J2" serial port:

Pin 1 - 3.3V (pin 1 has a white stripe next to it)
Pin 2 - RXD (from serial terminal program to NSLU2)
Pin 3 - TXD (from NSLU2 to serial terminal program)
Pin 4 - GND

By default, both Redboot and the Linux kernel use 115200,8,n,1 settings.

As I said, you need an RS232 level shifter (to convert TTL levels to +/-12V as needed by RS232 serial ports. I believe both Maxim and Dallas Semiconductor sell the chips. Or, the converters could be there as 'off the shelf' adapters (for developers) I suppose.

to:
Pinout of the J2 serial port
Pin 13.3V (pin 1 has a white stripe next to it)
Pin 2RXD (from serial terminal program to NSLU2)
Pin 3TXD (from NSLU2 to serial terminal program)
Pin 4GND
Changed lines 14-18 from:

[http://groups.yahoo.com/group/nslu2-linux/message/87]

to:

By default, both Redboot and the Linux kernel use 115200,8,N,1 settings.

Set DTR drop time to 0, and "modem has DCD line" to no, unless you know that your serial adapter ties DCD to DTR.

Make sure that your terminal program does not send a modem init string and that you have set it to software flow control, not hardware.

Changed line 20 from:

Location of the second receive only serial port:

to:

See HowTo.AddASerialPort for details on adding a serial converter to allow usage of the serial port.

Changed lines 22-25 from:

RXD - Right side of R128
RTS - NC
CTS - Left side of R142
TXD - NC\\

to:

[http://groups.yahoo.com/group/nslu2-linux/message/87]

Added lines 24-29:
Location of the second receive only serial port
RXDRight side of R128
RTSNC
TXDLeft side of R142
CTSNC
September 20, 2004, at 04:17 PM by tman --
Changed line 24 from:

Pinout for the second receive only serial port:

to:

Location of the second receive only serial port:

September 20, 2004, at 04:16 PM by tman --
Changed lines 22-32 from:

[http://groups.yahoo.com/group/nslu2-linux/message/87]

to:

[http://groups.yahoo.com/group/nslu2-linux/message/87]

Pinout for the second receive only serial port:

RXD - Right side of R128
RTS - NC
CTS - Left side of R142
TXD - NC

[http://groups.yahoo.com/group/nslu2-linux/message/488]

September 17, 2004, at 07:47 PM by Pete Verdon --
Added lines 18-21:

Pin 1 is the left-hand pin.

NB: In the photo above, a set of header pins has been attached to J2. As sold, J2 consists only of a series of solder pads.

September 16, 2004, at 05:24 AM by IN --
Changed lines 11-12 from:

As I said, you need an RS232? level shifter (to convert TTL levels to +/-12V as needed by RS232? serial ports. I believe both Maxim

to:

As I said, you need an RS232 level shifter (to convert TTL levels to +/-12V as needed by RS232 serial ports. I believe both Maxim

September 14, 2004, at 10:12 PM by ka6sox --
Added lines 16-17:
September 13, 2004, at 05:49 AM by ka6sox --
Changed lines 3-5 from:

Pin 1 - 3.3V Pin 2 - RXD (from serial terminal program to NSLU2) Pin 3 - TXD (from NSLU2 to serial terminal program)

to:

Pin 1 - 3.3V (pin 1 has a white stripe next to it)
Pin 2 - RXD (from serial terminal program to NSLU2)
Pin 3 - TXD (from NSLU2 to serial terminal program)\\

Changed line 12 from:

+/-12V as needed by RS232? serial ports. I believe both Maxxim (sp?)

to:

+/-12V as needed by RS232? serial ports. I believe both Maxim

Added lines 15-16:

[http://groups.yahoo.com/group/nslu2-linux/message/87]

September 13, 2004, at 05:47 AM by ka6sox --
Changed lines 1-14 from:
to:

Here's the pinout for the "J2" serial port:

Pin 1 - 3.3V Pin 2 - RXD (from serial terminal program to NSLU2) Pin 3 - TXD (from NSLU2 to serial terminal program) Pin 4 - GND

By default, both Redboot and the Linux kernel use 115200,8,n,1 settings.

As I said, you need an RS232? level shifter (to convert TTL levels to +/-12V as needed by RS232? serial ports. I believe both Maxxim (sp?) and Dallas Semiconductor sell the chips. Or, the converters could be there as 'off the shelf' adapters (for developers) I suppose.

view · edit · print · history · Last edited by Pete.
Based on work by johnnywhoo_DeleteThis_AT_gmx_net, tman, kivper, Pete Verdon, IN, and ka6sox.
Originally by ka6sox.
Page last modified on May 24, 2008, at 05:24 PM