Serial and powersupply cabling

For every hardware application a specific cable will have to be made.  We can't think of every cable config, simply because we don't have every piece of equipment available.  The best we can do is to supply as much information as we can to support you, and to share this information.

The cable kit contains all cables to connect the kit to a laptop pc.  There are 2 types of cable kits, type 1 and type 2.

cable kit type 1
( Or click here for a 1000*700 picture.)

cable kit type 2

Here is a description of cable kit type 2 for use with the GPS kit


A Y-kabel: GPS kit to laptop

The purpose of a Y cable is to:
1 - transport the serial signals from the GPS kit receiver RJ45 connector to the pc/laptop.
2 - supply the GPS kit with 5V tapped from the mouse/keyboard connector of the laptop.

The mouse plug of your laptop becomes unusable to actually connect an external mouse, so we presume you use the internal mousepad or trackball.

What we need is:

An RJ45 connector with a longer cable to connect to the GPS kit.
A DB9 connector, female with a short piece of cable to connect to the serial port.
A mini-DIN connector with a short piece of cable, for supplying 5V to the GPS kit.

RJ45 modular plugconnector to the GPS kit.

The signals on the contacts and (if you use the supplied blue cable in the cable-kit) the colors of this cable.  If you use another cable the colors are not applicable - please find them out by measuring with a contact tester or ohmmeter!

For this cable config we only use the bold printed wires.

 contact   direction (GPS)    level   description 
1 output  RS232  1 PPS signal on RS232 level. 
2 output RS232 NMEA data port output.
3 input RS232 NMEA data port input.
4 output TTL 10kHz square wave locked to GPS timebase.
5 input RS232 2e serial port for DGPS receiver. 
6 output TTL 1 PPS signal on TTL level.
7 both ground ground, for both RS232 port and power supply. 
8 input supply  Supply. +5V regulated or +10 to +25V unregulated, depending on pos. of  jumper SW5. 

Remove the isolation over a length of ca. 4cm and cut the wires you don't need.  Put a 10cm piece of 20mm thermal crimp tube over the cable to finish the cable when you are done.

The min-DIN or USB cable to the keyboard/mouse or USB connector of the laptop.

This is only used to tap the 5V power supply from the laptop for feeding the GPS receiver.
We can't supply you with information on the wire colors - you have to find this out yourseld by measuring with a multimeter or wire tester/beeper.  The wires we need are 3 (+5V) and 4 (ground).

de buitenste pinnen (3 en 4) zijn de voeding

Cut the cable on a reasonable length, say 25cm, strip the end, measure the wires we need and remove the other wires.

The USB connector to the USB connector of the PC/laptop

DB9 female connector to the serial port of the laptop.

The signals on the contacts and - if you use the supplied blue cable from the cablekit - colors of the wires.

We use onle the bold printed wires in this cable.

 contact   direction (PC)     level     description
1 input RS232 CD (Carrier Detect)
2 input RS232 RXD (Receive data)
3 output RS232 TXD (Transmit data)
4 uitgang RS232  DTR (Data Terminal Ready) 
5 both ground Common
6 input RS232 DSR (Data Set Ready)
7 output RS232 RTS (Request to send)
8 input RS232 CTS (Clear to send)
9 input RS232 RI (Ring Indicator)


Cut the cable on a reasonable length, say 25cm, strip the end, measure the wires we need and remove the other wires.

The wiring of the Y cable should look like this:

GPS RJ45 connector pin 2 --> DB9 connector pin 2 (data to laptop)
GPS RJ45 connector pin 3 --> DB9 connector pin 3 (data from laptop)
GPS RJ45 connector pin 7 --> DB9 connector pin 5 and mini-DIN pin 4 (ground) or USB 0V
GPS RJ45 connector pin 8 --> mini-DIN pin 3 (+5V) or USB +5V

Click here to see a diagram of the cabling

Isolate the solder joints with thin thermal shrinking tube and put the larger tube over the joint.

Check the cable on correct wring with a multimeter, and also for short circuits.  Put the SW5 jumper in the 5V position and connect the cable to the GPS kit, the laptop serial port and the keyboard/mouse port.

You should be able to measure 5V on the SW5 jumper, and the MAX232 ic should generate + and -9,5V.  See the test procedure.

When this is all correct you can install the GPS module (after temporary removing all cables) and we should be able to see the serial NMEA data coming out of the GPS kit, for example with hyperterm (4800bd 8n1).