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Tips and questions relating to the GPS modules from SFE
By Rimfire
#53379
I am new to this world of GPS's.
The other day a fellow ham radio operator gave me four ET-102
GPS RECEIVER ENGINE BOARDs, along with 1 Trimble Active Antennas.
The ET-102 is identical to the GPS-00577 GPS unit.
Knowing little about GPS boards and how they are connected to my
home computer. So I started reading the Product guide that came with
the boards. I hooked one of the boards up to serial cable (DB9-M to
DB9-F) and made sure the computer can see the cable, and it did.
I mounted the GPS boards on a breadboard and wired the board to
a DB9-F with the following connections. pin 10 of GPS board to pin 5
of DB9-F, pin 11 of GPS board to pin 2 of DB9-F, pin 12 of GPS board
to pin 3 of DB9-F. Connected antenna to GPS board, and applied
5vdc (regulated) to pin 2 of GPS board.
Prior to doing the above, I download two programs that was told would
function with the ET-102/ER-102 board. They are GPS-INFO-V1.03
and SirFGPSTweaker. I loaded the programs into my computer and they
setup perfectly.
I then loaded/ran the GPS-INFO-V1.03 program and applied power to
the GPS board. I told the program to scan for port that the GPS board
and serial cable were using. It scanned both port 1 and 3, and came
back and said "NO DEVICE".
At this point I also tried using a "serial to USB" cable and still no results.

My question is.....
Is there something else that I didn't connect, wire correctly?
I have other equipment that uses the USB ports, and they work perfectly.

Any help in getting these board hooked up correctly and working would
be appreciated, and any other information you need I can give to you.
Can post answer here or e-mail me at: wa6ddf@arrl.net.

RIMFIRE :roll:
By rtxo
#53506
the et-102 uses TTL (transistor transistor logic) level
signalling, and not RS-232 level signalling. You will
need at minimum a MAX-232 style chip to do the
level translation between a PC with RS-232 and
the et-102.

//rtxo//
By Rimfire
#53511
rtxo wrote:the et-102 uses TTL (transistor transistor logic) level
signalling, and not RS-232 level signalling. You will
need at minimum a MAX-232 style chip to do the
level translation between a PC with RS-232 and
the et-102.

//rtxo//
And not being familiar with such circuits, I decided to find and buy
a TTL to RS232 unit. I purchased the "FT232BM based TTL to RS232 via
USB port" unit. I was told that the unit would do exactly what I want.
Thanks
By Rimfire
#53911
And not being familiar with such circuits, I decided to find and buy
a TTL to RS232 unit. I purchased the "FT232BM based TTL to RS232 via
USB port" unit. I was told that the unit would do exactly what I want.
I know that pins 10,11,12 go to the DB-9F, but not sure where do pins 1 thru 9 on the ET-102 go. :(

Rimfire