Isnt' this interface better and cheaper?

[Zibri]

Hello everyone!
Since I had an URC 7560 laying around I was reading this forum to learn something more about it.

I also saw the various JP1 interfaces.
All they are (if I'm not mistaken) is an I2c to parallel (or usb) interface!

So, I was thinking, why not using something like this?


It can be found on ebay for a few bucks!

[cauer29]

Hello everyone!
Since I had an URC 7560 laying around I was reading this forum to learn something more about it.

I also saw the various JP1 interfaces.
All they are (if I'm not mistaken) is an I2c to parallel (or usb) interface!

So, I was thinking, why not using something like this?


It can be found on ebay for a few bucks!

Hmm...where to start...

JP1 eeprom. There is exactly zero support for using this as a USB to JP1 eeprom interface. All of the current software requires either direct access to the hardware parallel or serial interface lines to manually bit-bang the I2C eeprom interface, or the deprecated Delcom USB to I2C convertor. Additionally, there are special requirements above and beyond the simple I2C, for a JP1 eeprom remote. Also need to make a cable from this board to the JP1 connector itself. You could eventually get it all working, but it would most definitely not be simpler what with re-writing the software for IR RMIR, etc. One more thing that I forgot to mention and that is that different JP1 eeprom remotes have different I/O voltage levels. So, you'd need some way to deal with the difference between the 4 cell 6V designs and the 2 cell 3V designs. The JP1 eeprom interfaces might seem trivial, but actually quite a bit of thought went into their design.

JP1.x flash. Well yes, this would probably work. You will need to connect RTS or DTR in addition to Tx and Rx. Also, you would need to fabricate a cable from this board to the JP1.x connector. There are numerous USB to ttl serial boards available that can fill this role without resorting to ebay. None of which are particularly suitable for the average JP1 user. Those skilled in tinkering with these sorts of boards, can save a few dollars, but for the masses, they're much better off sticking with a ready-made cable.

A.A.

[The Robman]

I don't know what price this part sells for on ebay, but you have to factor in the time and effort that would be needed to make a JP1 cable from it, plus the cost of the additional parts (cable, connector, etc).

The current design calls for a $20 cable and a $0.90 cent connector. And the only assembly you have to do is to remove the crimped ends from the flat 1x6 connector and insert them into the rectangular 2x3 connector.

I just estimated the shipping cost to my zip code and it came out to $2.80 for 1st class, which would give a total cost of $23.70.

[Zibri]

Hmm I'm in Italy, great hacking and coding skills but no building/soldering prototyping skills at all

Do you knopw where can I find a JP1 cable (usb) for my URC 7560?

I can program it using wav files but I wish to backup all the internal codes and clean all unneeded ones.

Oh.. the above interface costs only $12 (if you are wondering).

This is the seller link: http://goo.gl/Wdeql

[Zibri]

About the current design, isn't the 232R a usb<>ttl converter?

Can a prolific 2303 be used instead?

[Zibri]

How about this?

http://goo.gl/wWo9R

[cauer29]

About the current design, isn't the 232R a usb<>ttl converter?

Can a prolific 2303 be used instead?

Usually yes. You will have to connect 4 pins, Tx, Rx, RTS, Gnd. Since you say that you don't have good soldering/prototyping skills, you may have some difficulty to make the cable from the board you showed to the JP1 connector.

A.A.

[mdavej]

Zibri,

There is no cheap serial/USB solution that will work for you. You have a JP1 EEPROM remote that requires the delcom cable or a JP1 EEPROM adapter.

If you have a parallel port, the simple parallel interface will work fine. You can build one of those for practically nothing.

If you only have USB ports, the absolute cheapest solution is something like THIS prolific based cable plus the EEPROM adapter from Tommy.

[Zibri]

@mdavej: I already have a lot of those cables/converters (that's why I talked about the pl2303) but they only have rx+tx+gnd.

EPROM adapter?

I still don't get it.
Isn't the bus available on the 6 pin connectr a simple I2c bus?

The first device I linked should be enough to "talk" i2c.

I also could make a very simple device (it's just pin to pin from vga port) to talk i2c using the VGA port on an NVIDIA soundcard if you want

I already coded a small program able to talk i2c using the vga or dvi port.

[Zibri]

@mdavej: I don't have a parralell port on my main pc. But I have it on my old pc and my very old notebook. I'll see what I can do. But I still think that IR.EXE should support the interface I posted on this thread. It's a very simple and cheap USB to everything device

[Zibri]

@cauer29: on then.. challenge accepted.

I ordered one (because I need that foir other projects too).

I will connect the i2c to the 6 pin connector and browse around.

If I will have time (I hope so) I will post any results here.

By the way, since the 6pin connector has an i2c bus directly connected to the cpu and eeprom, and since the i2c bus is a very simple and basic bus I already dealt with, it should be really simple to write a simple software to read (and write) the remote eeprom.

And with that interface there will be no need to manually do the bit-banging.

[mdavej]

@mdavej: I don't have a parralell port on my main pc. But I have it on my old pc and my very old notebook. I'll see what I can do. But I still think that IR.EXE should support the interface I posted on this thread. It's a very simple and cheap USB to everything device

Perhaps IR will support your interface. But the fact remains that your remote won't work with it. JP1 EEPROM remotes simply don't work with serial interfaces alone.

BTW, the other side of the prolific board has RTS, CTS and other signals. It works perfectly well as a JP1.x cable.

In any case it seems like a dead end to me. Am I missing something?

[cauer29]

@cauer29: on then.. challenge accepted.

I ordered one (because I need that foir other projects too).

I will connect the i2c to the 6 pin connector and browse around.

If I will have time (I hope so) I will post any results here.

By the way, since the 6pin connector has an i2c bus directly connected to the cpu and eeprom, and since the i2c bus is a very simple and basic bus I already dealt with, it should be really simple to write a simple software to read (and write) the remote eeprom.

And with that interface there will be no need to manually do the bit-banging.

Zibri,

Yes, the first board in the picture can do I2C in addition to serial. So, in theory you could use it for either. The issues aside from no support for a non-standard JP1 eeprom cable in the available software, is that you need to deal with differing battery voltages. If your remote uses a 2 cell battery, then the I2C needs to be configured for 3V logic levels. If it's a 4 cell remote, then you need 6V. All of the existing JP1 eeprom cable designs deal with that difference.

Then there is also the matter of the reset line. It's been a long time, but my memory is that you must drive the JP1 reset line low in order to allow communication to the I2C eeprom. Can this board be setup to do that?

Once you've got all that taken care of, then you need to write software to read the eeprom. It would be best to save it to a file compatible with the standard JP1 tools, IR or RMIR.

You can do all this I'm certain, as I did it some years ago, but it was so cumbersome to use compared to the fully integrated download/modify/upload capabilities of IR and RMIR, I ended up making a real JP1 cable.

[The Robman]

If Zibri were to be able to rig up some sort of interface that works with a new program, would adding support to IR.exe be as simple as adding a new, or modifying an old, DLL?

[cauer29]

If Zibri were to be able to rig up some sort of interface that works with a new program, would adding support to IR.exe be as simple as adding a new, or modifying an old, DLL?

Rob,

I'm not much of a software guy, but from what I know of the FTDI combo chip, yes a new or modified existing DLL would be in order. The exact details may be tricky, as it is just one chip that can do I2C for JP1 eeprom or standard UART for JP1.x. Normally we use the FTDI VCP drivers. So, I'm not certain how software switches the chip from serial to I2C. Perhaps FTDI added the extra functions to their driver. I hope that I2C doesn't require the native non-VCP driver, else that will be a bit of bother switching back and forth every time you want to go from JP1 to JP1.x.

In any case, to be a truly universal JP1.anything, we'd need two different cables from the PCBA. One for JP1 and another for JP1.x. Now that I think about it, I've done this already for standard non-USB serial port. It wasn't of much interest since nobody has real motherboard serial ports anymore.

A.A.