DIY pc-interface for Cressi Archimede I/II / Apex Quantum / Tusa IQ-700 / Nitek Duo

[dexter98]

Sorry guys, but no schematic.... yet! But the 'problem' is brought down to a few options.

I have been searching for information / a schematic of the the pc interface for the Apeks Quantum (which seems to be the same for the cressi archimede I/II, Tusa IQ-700 and the DiveRite Nitek Duo), but no information at all seems to be freely available.

Since it seems to be nothing more than a 'standard' USB-to-serial converter (which can be bought for $5) in a big clothes pin, it's standard price of about $120 is really way too high.


Since no schematics exist, I already did a little investigation on my own:

- The Apeks Quantum, Tusa IQ-700, Nitek Duo, Cressi Archimedi I and II all use exactly the same computer interface (all Seiko computers).

- The interface is actually nothing more than a USB-to-serial converter based on a PL-2303 from Prolific, which is used in many 'standard' USB-to-RS232 (DB-9) converters, and a level converter.

- The PL-2303 is however 'reprogrammed' to have it's own VID/PID (vendor ID/product ID; it is used to identify the type of the hardware).

- The software package supplied by TUSA also contians a Windows XP driver, from which the correct VID/PID can be retreived. VID=04b8 PID=0522 for the Seiko interface, while a 'standard' PL-2303 has VID=067b PID=2303.

- The pc-software connects to the USB device through it's VID/PID, so a 'standard' USB-to-serial converter cannot be used without reprogramming it. A simple programming tool is available from Prolific, but it is only available to suppliers and not to end-users.

- The pc-software from the Apeks/Tusa/Dive-rite does not have the connection tab in the options dialog and can therefore only connect to the USB device.

- The pc-software from Cressi (which also seems to be a newer version than the ones supplied by the other companies), allows to select a connection (USB / COM 1/2/3/4).

- If the serial communication protocol of all computers is the same and doesn't contain any product ID, a simple serial interface like already available for the Vyper, can probably be used for the communication in combination with the Cressi software.



So, actually, there are currently five options:

- The pc-software for the Cressi can also be used for the other computers. A very simple RS232 <=> DC interface (like already freely available for the Vyper) will be sufficient.

- The VID/PID in the pc-software of the other computers is changed using a hex-editor / decompiler, so the pc-software can communicate with 'standard' PL-2303-based USB-to-serial. On this converter, a simple RS232 <=> DC interface is connected.

- Activate the extra communications tab in the pc-software for the Apeks/Tusa/DiveRite by 'hacking' the pc-software.

- The VID/PID of a 'standard' USB-to-serial converter is reprogrammed using the appropriate Prolific tool. Then, the unaltered pc-software can be used, in combination with the simple RS232 <=> DC interface connected.

- Program a PIC/AVR microcontroller with an USB-interface to mimic a PL-2303, but with the 'custom' VID/PID.


Any ideas how to go on, how to reprogram the PL2303 or other information on this interface is very welcome.

If I get a working DIY interface, I'm going to share the information (schematic / software) about the interface available on my website with other Seiko-based dive computer owners who want to build their own interface.

 

[RisingPhoenix]

I am actually getting a hold of hoeful;ly in the next couple of days one of the serial versions of the cressi cable to try and get pin outs for if its helpful..

 

[DomaNitrogen]

Thanks guys... keep us posted

 

[dexter98]

@RisingPhoenix:

Great! This would certainly help us! If you could post the pinning/schematic here, we can proceed to 'the next step'.

 

[RisingPhoenix]

Well guys, maybe time to scream..

I am electronics by trade yep, but i just ripped apart the serial version of a cressi downloader...

And well, it aint pretty, net even 1/10th as straight forward looking as the new usb model..

Even worse, check out the PCB

Sorry guys, but IMNSHO Sweet FA chance of getting this working cheap asa a DIY!!

Steve

 

[dexter98]

Great! Good info!
As I'm interpreting it correctly: just a simple level-shifter as already suspected. Fortunately not a microcontroller that does some nasty protocol conversion (although I cannot read the type-number on the chip; that certainly would clarify a lot). The PCB may look complicated, but that's only because of the little room and strange shape

2 questions:
what is the power connector doing there? do you have to connect an external adapter to use this interace?
where are the 2 connection points to the dive computer?

But, erh... do you suggest you already dismantled an USB version also?

 

[RisingPhoenix]

the "power connector" is actually what connects to the computers two terminals, there is another annoying molded plastic bit that you sit the computer on that plugs into this connector..

If you want a higher res shot, pm me with an email address and i'll send you one..

Steve

 

[dexter98]

Ok, I have sent you my email-address in a private message to you.

 

[dexter98]

Ok, a little update on my progress:

I found out that the PC-software maybe doesn't connect to the USB interface directly via its VID/PID, but on another way where the VID/PID is not important at all.

I have connected a standard USB-to-serial interface and altered the driver (.inf) from the TUSA software to pick up this interface at its own VID/PID, instead of the SEIKO VID/PID. The driver (as expected) does not complain at all and the device is correctly enumerated.

Now the good part:
All the SEIKO software (Apeks, TUSA, Cressi-sub) with support for the USB interface directly give an 'unable to connect' message if no USB interface is connected. With the official driver for the cable, this is still the case.

Strangely enough, when I install the altered TUSA driver, the software suddenly does not give the 'unable to connect' message directly, but after a few seconds, which implies that it sees the interface! There is still no data coming out, but it is at least a start.

My question to other SEIKO-based DC owners: If you connect the computer to the interface, but forget to set in the PC mode, is the behavior the same as described (wait a few seconds and then the 'unable to connect' message)?

 

[blibecap]

Hi
The docking station for the Apeks plus- Nitek duo is a little more complicated than originally thought. They use a double sided board and 9 chips with associated circuits. I was able to purchase one on ebay a while back for about $90. It works nice but would be hard to figure out as some of the components are not marked as to the values. I have taken some pictures and attached them here. It uses all 4 wires in the usb and only 2 contacts on the dive computer. If anyone really wants to try to reproduce this I have pictures, and would be glad to share them with you.
Bill