So as I mentioned in another post I have one of pca's tuner kits assembled. It powers up and doesn't explode or smoke but the empeg doesn't see it. I've checked it as far as the limited debugging notes of the assembly instructions go - the 5V and 9V regulators are indeed putting out the correct voltages. I have visually inspected my work a number of times and can't find any assembly mistakes. I'm certain the 2 or 3 parts left over served no real purpose

Now it would seem to me that the empeg should recognize the tuner if the path from the empeg to the PIC is alive. Looking at the parts list this would include the regulators, the MAX1489E level converter (IC5) and the PIC CPU (IC4) plus what ever clocks the PIC and resets it. What I don't see it which chip or transitor converts from logic-levels to RS232 (the 1489 goes from RS232 to logic-levels).

I know the schematic of the tuner can not be revealed as it is the property of empeg or whoever owns them now. But can anyone with knowledge of the design tell me if my assumptions in the above paragraph are correct? Likewise can anyone with a working tuner describe any test-points and signals that would allow me to narrow down the problem area? Aside from my DVM I also have a scope.

-- Craig

Curious you should say this: I just had my first (out of 8) build failures, with exactly the same failure mode you are observing.

The LED indicates that the tuner module has received the correct initialisation data from the empeg. It does not, however, imply a handshake with the player, so as you and I discover, it could be a fully functional tuner that is not being recognised by the player due to the player thinking there's no module attached.

Using a scope on the RX and TX lines at the connector to the player, my module receives a stream of data packets during startup of the player, to which it replies with a stream of packets. The player is not seeing this, for some reason. To eliminate the player from the equation, I tried it with a known good factory unit, which then is recognised - so it's not that.

The level convertor chip is an additional Serial Port for the player unit, which is currently unused in the player software. The software for the PIC on the module has support built in to use this port, along with the 12V sense inputs and the two solid-state relays - but the support is not there in the player software to drive them.

The RX and TX data lines between the player and the module are TR4 and 5.

What I need to do is do a capture of the incoming and outgoing data stream on a working, recognised module then compare it with this dead one. Will let you know what I discover.

Here is a Hijack trick for both of you to try with your malfunctioning tuners:

In the player's config.ini file, add the following:

[hijack]
fake_tuner=1

This causes Hijack to force the player to "see" a tuner module, even when one is not (apparently) present. If for any reason a real tuner responds, Hijack then quietly bows out of the handshake, leaving everything functional.

It might provide enough of a timing bend to cause things to work, or it might at least provide some more info. There is also a trace_tuner=1 flag to dump out all of the packets sent/received onto the console serial port.

Cheers

You see? He's got a fix for just about everything!

Worra nice bloke