Build a JP1.x/JP2 cable using an FTDI Serial Converter Cable

[The Robman]

Hi, I spotted this $9 USB to serial converter and was wondering if you think it would work:

https://www.dealextreme.com/p/usb-to-ua ... 872?item=2

If so, in order to connect the cable correctly, what are the pinouts of the 6 pin connector for a JP1.3 remote? The other docs just say the color connections (AFAIK). The individual connectors could be super-glued together.

Thanks.

The instructions are color based because they're for a specific cable, so that's the easiest way to identify them.

The part that you're looking at looks similar to the parts that we used to get from Nokia CA-42 phone cables.

Read this thread for more info:
http://www.hifi-remote.com/forums/viewtopic.php?t=13877

And the main doc is here:
http://www.hifi-remote.com/forums/dload ... e_id=10706

Here's the pinout:
1 - (empty)
2 - reset
3 - ground
4 - Rx
5 - (empty)
6 - Tx

I can see Gnd, Tx and Rx in the DealExtreme pics, but I can't see Reset.

Here's the data sheet for the CPU:
http://www.silabs.com/Support%20Documen ... cp2102.pdf

The data sheet shows that Reset is on pin 9, so that should help you figure out where to put the wire for pin #2.

[cauer29]

The data sheet shows that Reset is on pin 9, so that should help you figure out where to put the wire for pin #2.

JP1.x pin 2 (reset) is connected to RTS on the FTDI cable. If the cp2102 based converter doesn't pin out RTS, I believe that DTR will also work. That's what some of the older JP1.x cables used.

A.A.

[dailyglen]

Thanks for the info; there must be a better cable. The reason I don't want to go with the recommended cable is I'm outside the US and Mouser charges $20 extra for shipping.

On eBay there are quite a few options with the search terms "usb ttl ft232 cable". Tommy says 3.3V is recommended but will 5V work too? Many Arduino cables are missing RTS (or DTS (can someone confirm if this works?)).

I ordered this cable (a few days ago; before posting) which has a 3.3V and 5V option but they never asked which voltage (or connector) I needed (I'm trying to rectify that):

http://www.ebay.com/itm/160833251035

It has the same colors as the recommended cable so hopefully it has the same pinout. I plan to cut the connector and glue it back-to back to create a 2x3 (less 1) connector (as I don't have a cheap supply of 2x3 connectors). With 5 pin connector it would be nice to put a key on pin 1 of the remote so that you can't incorrectly plug in the cable into the remote -- I fried a remote doing this while overtired. Do people know what these keys are called or where to order them from? Is there a better way to create a keyed connector?

Having $10 connector would really make JP1 a lot more accessible for a lot of people. If this all works you can get atlas remotes for about $10 and a cable for $10 and I could convert over quite a few of my friends and family to JP1!

Thanks.

[The Robman]

Thanks for the info; there must be a better cable. The reason I don't want to go with the recommended cable is I'm outside the US and Mouser charges $20 extra for shipping.
...
Having $10 connector would really make JP1 a lot more accessible for a lot of people. If this all works you can get atlas remotes for about $10 and a cable for $10 and I could convert over quite a few of my friends and family to JP1!

Why don't you try going with one of the Nokia phone cables from DealExtreme (here or here). The site says "free shipping" and the cables come from China, so I imagine the shipping would be free to you also. The price is just under €4 Euro (or $4.40 USD). Then follow these instructions for modifying the cable.

You would still need to find your own 4 conductor cable and IDC connector.

[dailyglen]

The issue with the Nokia solution is I can't find a cheap source for the 2x3 IDC connector. I'm planning on using this method posted by underquark to convert the 1x6 IDC connector into a 2x3:

http://www.hifi-remote.com/forums/dload ... e_id=10998

This seems pretty easy to do.

[cauer29]

Thanks for the info; there must be a better cable. The reason I don't want to go with the recommended cable is I'm outside the US and Mouser charges $20 extra for shipping.

On eBay there are quite a few options with the search terms "usb ttl ft232 cable". Tommy says 3.3V is recommended but will 5V work too? Many Arduino cables are missing RTS (or DTS (can someone confirm if this works?)).

I ordered this cable (a few days ago; before posting) which has a 3.3V and 5V option but they never asked which voltage (or connector) I needed (I'm trying to rectify that):

http://www.ebay.com/itm/160833251035

It has the same colors as the recommended cable so hopefully it has the same pinout. I plan to cut the connector and glue it back-to back to create a 2x3 (less 1) connector (as I don't have a cheap supply of 2x3 connectors). With 5 pin connector it would be nice to put a key on pin 1 of the remote so that you can't incorrectly plug in the cable into the remote -- I fried a remote doing this while overtired. Do people know what these keys are called or where to order them from? Is there a better way to create a keyed connector?

Having $10 connector would really make JP1 a lot more accessible for a lot of people. If this all works you can get atlas remotes for about $10 and a cable for $10 and I could convert over quite a few of my friends and family to JP1!

Thanks.

The 5V version of the cable will probably work, but is not ideal. There are 2 potential issues though. The first is for data sent by the remote to the cable. Since JP1.x remotes are always 3V or 3.3V levels at the CPU, it is possible that the remote cannot drive to a high enough voltage for the IC in the cable to detect a logic 1. Fortunately, based on the specs for the cable, the threshold voltage is only ~1.5V. So, that direction shouldn't cause any issue.

Then there is the issue of the cable driving 5V logic level into the remote's CPU that is only powered by 3 or 3.3V. It would be best to put some series resistance in the cable's Tx and RTS lines to limit the current flow into the remote's ESD protection structures. 330 or 470 ohms should limit the current sufficiently without hurting the rise/fall times on the 38.4K baud serial baud rate.

No need to do that if you end up getting a 3.3V cable.

A.A.

[The Robman]

The issue with the Nokia solution is I can't find a cheap source for the 2x3 IDC connector.

Do you have any old hard drive cables? If you do, you could cut off a 6-hole portion of the IDC connector to make your JP1 connector.

[jgfarrell]

Hi, dailyglen.

I'm outside the US as well, and didn't want to pay the high freight charges either, so I bought this cable:
http://www.ebay.com/itm/280910040147
which I'm sure is identical to your cable:
http://www.ebay.com/itm/160833251035

This is basically just a summary of what others have posted above...

I followed Underquark's method:
http://www.hifi-remote.com/forums/dload ... e_id=10998
with the exception that after removing the red wire and cutting the connector where the red wire resided, I then removed all the remaining wires and glued the two pieces together with the smooth edges aligned and the tabs facing outward, allowing future access to the tabs if necessary.

Then I used Tommy Tyler's document:
http://www.hifi-remote.com/forums/dload ... e_id=10864
to figure out where to re-insert the wires.

I just used a tiny jeweller's screwdriver to lift the tabs, and a large Olfa-style knife (the kind with snap-off blade sections) to cut the connector, which also worked well to shave off the rough cut edges.

Cut the unused wires at slightly different lengths just to remove the possibility that they might short together.

A piece of heat-shrink tubing applied high enough up the connector to leave the tabs exposed gave the exposed wires a bit of mechanical support, and tidied up the appearance as well. so I was left with a cable that has a notch out of the corner marking Pin 1 as Underquark described.

Download drivers for XP here: (not needed for Windows 7, I believe)
http://www.ftdichip.com/Drivers/VCP.htm

Works great!

Hope this helps...
John

[dailyglen]

Hi,

Thanks for the summary. I like your tips of using the Olfa knife and having the tabs facing outwards. I'll give it a try once my cable arrives.

Cheers

[brfransen]

Can this FTDI cable be used with http://www.diygadget.com/jp1-2-1-3-to-jp1-adapter.html for older JP1 remotes? Does that adapter just change the pins or is there some other electronics?

Thanks!

[cauer29]

Can this FTDI cable be used with http://www.diygadget.com/jp1-2-1-3-to-jp1-adapter.html for older JP1 remotes? Does that adapter just change the pins or is there some other electronics?

Yes, that adapter will work with the FTDI cable. The adapter has a small CPU inside that does the work of translating JP1 to JP1.3. It is more than simply changing pins.

A.A.

[dailyglen]

Hi,

I got my ebay USB/TTL cable today and did the modifications as summarized by jgfarrell above. I tested the cable with the jp1xtest.exe program and it works fine. I like that it has an obvious key for pin one (a notch in the connector) and it was only $12 shipped.

Thanks for the great pointers and all the work you guys have done with JP1.

Cheers

[aclinml]

Yes, that adapter will work with the FTDI cable. The adapter has a small CPU inside that does the work of translating JP1 to JP1.3. It is more than simply changing pins.

A.A.

OK, I have a One For All JP1 remote (Cinema 7 URC-7800B00).

I have followed the instructions in Tommy's PDF "AN EASIER WAY TO BUILD YOUR OWN JP1.2/3 (FLASH) INTERFACE" using the cable from Mouser with crimps removed from there original housing. I also used the connector housing recommended from Mouser

Item 1 is a TTL-232R-3V3 Serial Converter Cable, Mouser part
number 895-TTL-232R-3V3, price $20.

Item 2 is a Connector Housing, 2x3 Pos DIL, Mouser
part number 855-M20-1070300, price $.15.

There were no problems in removing the crimped ends and inserting them into the new connector housing.

I also purchased the JP1 adapter from DIYGadgets ( http://www.diygadget.com/jp1-2-1-3-to-jp1-adapter.html )

I downloaded and installed the FTDI drivers from this link http://www.ftdichip.com/Drivers/VCP.htm

I am running Windows 7 64 bit so this is the driver (2.08.24) I installed. The drivers downloaded and installed with no problems, at least that's what Device Manger tells me..

That's the history here is the problem, when I run the Interface Check for IR Release 8.03, I get the following error message

. OPEN DEVICE FAILED(Last Error=3) Which I assume means the program doesn't see my remote.

Do I have a cable problem, an adapter problem, a driver problem, a remote problem or (most likely) a user problem? I have been borrowing this cable ( http://www.diygadget.com/jp1-1-1-1-2-1- ... cable.html ) from a friend and it works with no problem. Unfortunately it is no longer available for purchase.

And does anyone have any idea what I could try before I give up on ever updating my remote again?

Thanks

[vickyg2003]

Do I have a cable problem, an adapter problem, a driver problem, a remote problem or (most likely) a user problem? I have been borrowing this cable (http://www.diygadget.com/jp1-1-1-1-2-1- ... cable.html) from a friend and it works with no problem. Unfortunately it is no longer available for purchase.

And does anyone have any idea what I could try before I give up on ever updating my remote again?

Thanks

I'm not a techie. I don't build my own stuff. Here is what a "non-techie" would do.

Don't rule out a battery problem. Low voltage is a problem. Uploading and downloading wears out the batteries quicker than you can imagine. If you've been experimenting a lot, or leaving your cable plugged in when not downloading this could very well be your problem.

If you are in the U.S, the next would be to see if anyone you know will let you read from their cable remote. Then you will know if the flash cable is working or not.


Those are the low-tech things you can try.

[nejpski]

Any comments on this cable now available from Ebay. Note: 3.3volts....and no 1x6 header.....instead 6 x 1s.

Price looks great. Does it appear it will work with Mods above for Less than $10 SHIPPED TO USA (FROM hK).

tHANKS

http://cgi.ebay.com/ws/eBayISAPI.dll?Vi ... 1101529602