JP1 Remotes

I just bought a urc-7780 and I did read that my old simple JP1 parallel cable wont work. Ok, i will build this jp1.2 new cable using tommy tyler design :
https://www.hifi-remote.com/forums/dload ... le_id=3585

In his document, I can read :
> If you have absolutely no interest in (now obsolete) JP1.1
> remotes you can omit R1, D1, and Q1.

so BKGD (pin 5) will be floating. right?

in the old simple jp1 cable RESET was on pin 5... (I hardly rembeber, but I think I did build this one : http://www.hifi-remote.com/jp1/simple/index.shtml )
so I don't understand wether RESET pin is usefull at all.

can I also omit Q3????

what is the DTR usefull for?

Is the ir.exe source code available somewhere, so I could read some jp1.2 I/O stuff????

thx...

Olivier

so BKGD (pin 5) will be floating. right?

Right.

can I also omit Q3????

No.

what is the DTR usefull for?

It is the reset signal.

Tommy

It is the reset signal.

ok, but what for? Is it really necessary to reset the remote before or after using the JP1.2 cable? In this case can I instead just remove the bateries each time I program the remote?

In your design, I also don't understand the R6, pullup from rx to DTR. Is this a way to detect the cable (from ir.exe point of view?) or some flow control ?

One more question : In JP1 parallel cable, 2 pins where connected to SDA and SCL of the eprom for simple i2c programming. In JP1.2 one talk to some rx/tx pin of the microcontroller wich in turn would have some firmware to program an i2c eeprom connected to him? is this right?

If so, your design is a simple transeiver (like MAX3232), except for the RESET thing (that I still don't understand). right?

Again, is the source code of IR.EXE available? This would ease the understanding of the whole thing.

Thx.

Olivier.

czo wrote:Is it really necessary to reset the remote before or after using the JP1.2 cable?

Yes. The communication must be started immediately (a few milliseconds if I remember correctly) after a reset or it won't work.

czo wrote: In your design, I also don't understand the R6, pullup from rx to DTR. Is this a way to detect the cable (from ir.exe point of view?) or some flow control ?

Neither.

The remote and the rs232 port don't operate at the same voltage, so the remote can't generate both high and low levels for the rs232 receive. So the interface has the remote pull rx down for low but float it for high, and the high voltage comes from DTR.

czo wrote: One more question : In JP1 parallel cable, 2 pins where connected to SDA and SCL of the eprom for simple i2c programming. In JP1.2 one talk to some rx/tx pin of the microcontroller wich in turn would have some firmware to program an i2c eeprom connected to him? is this right?

No. There is no i2c at all in the JP1.2 remotes. The memory being programmed is inside the remote's CPU chip. It does have firmware to program that memory in response to signals on the JP1.2 interface.

czo wrote: If so, your design is a simple transeiver (like MAX3232), except for the RESET thing (that I still don't understand). right?

Probably (but I don't know what MAX3232 is). Tommy's design connects an output from the remote to an rs232 input and connects two rs232 outputs to remote inputs (including reset), but does all that in a way that works despite the two sides operating at different voltage levels.

czo wrote: Again, is the source code of IR.EXE available? This would ease the understanding of the whole thing.

Sorry. The relevant part of that source isn't available.

Sorry. The relevant part of that source isn't available.

I'm very very very disapointed that the source is not open source....

Could we know the reason why?

I've been very happy with my old urc7560 for years. I had not problems with the parralell JP1 cable and IR.EXE so I did not investigate... I did think it was free software....

I should have considered buying a logitech harmony then. instead of this new urc7780....

Thx anyway...

Olivier.

czo wrote:I'm very very very disapointed that the source is not open source....
...
I should have considered buying a logitech harmony then. instead of this new urc7780....

... because the Logitech Harmony provides you with open source code?

czo wrote:I've been very happy with my old urc7560 for years. I had not problems with the parralell JP1 cable and IR.EXE so I did not investigate... I did think it was free software....

All the JP1 software is free, as is the support we provide here, so I do not understand your comment. You were able to use the old JP1 interface with your URC-7560 without problems, and I'll wager you never looked at the source code.

If you build the JP1.2 interface per Tommy's suggestions, then you should also be able to use your new URC-7780 as successfully as you did your URC-7560. However, please understand that we are still developing the tools for JP1.2, so you may encounter some problems. For example, the RDF file for the URC-7780 is still a work in progress.

because the Logitech Harmony provides you with open source code?

No, and that why I did not even look at it....

All the JP1 software is free

I was talking about free as in a "free speech" not a "free beer". (see http://www.gnu.org/philosophy/free-sw.html). I'm involved in free software since many years and contribute to many open source projects. Open source has the advatage (among many other) to improve developement using contribution of many people with different skills.

Again, could I know the reason why it's closed source?

Anyway, I dont want to hurt anybody feelings. I am thankful to all of you.

Thx.

Olivier.