Universal Sync Connection using CF to serial or USB?

Since Pharos makes CF-to-serial adapter and serial-to-USB cable, I keep thinking about making a simple mod to connect a standard serial port to Pharos' proprietary serial connector. I strongly believe it can be done and it would be come a universal sync connection. For the serial-to-USB adapter, Pharos does provide drivers for host PCs. Effectively, CF end at our CE devices becomes a slave port. Any comments?

Edited by CAuser 2008-04-17 7:43 PM






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CF2Serial&Serial2USB.JPG (37KB - 11 downloads)

I guess I need to make a crossover connection just like the null modem cable for Skeye.pad. Then, finding out the pin designations is key.

How much would the parts cost?

The adapter costs $24.41+$4.99 S/H. http://www.amazon.com/gp/offer-listing/B000IN04G4/ref=sr_1_olp_1?ie=UTF8&s=electronics&qid=1208541922&sr=8-1

This guy did it by opening the case and installed a regular serial connector!
http://www.aximsite.com/boards/x50-x51-accessories/100769-there-usable-rs232-compliant-cable-x50v-hyperterminal-like-software.html
My-O-my - got it less than 24 hours after ordering from Dell.ca - and it's a true CF SERIAL (TTL only) card!!!
Here's what my X50v sees:
PNP name: CF_CARD-GENERIC-A569
Port: comm 4
Dev ID: 43
Socket: 0
Driver: serial.dll
Rgy entry: drivers\pcmcia\serial

So now I'm trying to carefully open the case so I can see what the pin connections are.
I DO know that even though there are 12 pins, they are doubled. There are actually only 6 pins used and the external cable connector that fits over the GPS module connector only has 6 wide pins inside.
There are two GND, 1-Vcc, Rx & Tx. I need to figure out what the 6th pin does.

UPDATE:
The serial chip inside the CF card is an Oxford Semicondictor OXCF950: http://www.oxsemi.com/oxford/documen...t/OXCF950.html
The CF card pinout:
(pin 1 is at the top of the picture)
1,2 - Gnd
3,4 - 3V
5,6 - Gnd
7,8 - Rx (0-3v into the CF card)
9,10 - Gnd
11,12 - Tx (0-3v to the GPS)

The following are not connected on the OXCF950 chip:
DTR, RTS
The following are tied to +3V on the OXCF950 chip:
RI,DCD,DSR,CTS

There is enough open space on the PCB to mount a MAX3232 (surface mount package) and to bring out the wires though the plastic housing to a DB9 mounted on the back. That way, you can still use the CF adapter with the Pharos GPS if you wanted to.

Another possibility?

I'm thinking about making a female CF to female CF transition using 2 female CF connectors and a 50-pin ribbon. The transition is then used together with a CF card reader to complete a CF (client) to USB (host) connection.

Edited by CAuser 2008-04-18 4:04 PM

I'm experimenting the setup to do file transfer instead of full sync that requires mod to the adapter.

Some internet pages indicate that the adapter and Pharos GPS-360/500 use the following pinout:
PIN#1 RXD
PIN#2 GND
PIN#3 TXD
PIN#4 GND
PIN#5 VCC (3.5-5.5V)
PIN#6 Unused

A null modem cable plus this adapter may provide the function of file transfer. Obviously, connecting RXD(TXD) to PIN#2(3) of a standard serial connector DB9 and their ground pins won't trigger a sync as ActiveSync requires a null modem cable with full handshaking.

Do I use MP900C or the host PC as a terminal and its terminal program to do the transfer? Simply put, do RXD, TXD, and GND connections (null modem with neither loop back nor handshaking) suffice for the file transfer?

Comments and suggestions are welcome. Thanks.

The pinouts in the previous post seem to be correct.

I have just breadboarded a Pharos GPS-500 in straight serial mode using a PS/2 cable (Pharos SKU# 033-0039) and a logic probe.

Pharos Pin #, PS/2 Pin #, Function, Remarks
1 5 RxD (?) Internal pull-up (?)
2 6 Gnd
3 3 TxD External 4.7 K ohm pull-up
4 6 Gnd
5 1 Vcc +5 V
6 2 ??? Uniform blinking signal (sync?)

BTW, this is intended for an autonomous model truck competing in a RoboMagellan contest. In this mode, it appears that neither loop back nor handshaking is required.