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Daisy wrote:
The tc4 seems to have grown to include extra outputs etc to control fans and heaters but if i only want to monitor i dont think i need to use these functions so when i by the kit do i need to solder all the headers and pins to these areas or can you leave them just blank?

Daisy wrote:Also what is the jeenode for and will i need to use this for my application with abourbon.

Daisy wrote:Last question is the gndpt on the tc4, does this need to be connected to the arduino or is this an extra gnd for adding extra things to the shield?

JimG wrote:

The grounding pins generally are only needed if you are using grounded thermocouples and also powering your Arduino from a non-grounded power supply. Wall warts and some computer chargers fit into this category. If you run from batteries, or from a power supply whose negative lead is at the same potential as the frame of the Hottop, then no external ground wire will be needed.

Jim

petershek wrote:


Hi Jim,

How should I connect the ground pin if I recorded such a shift in temperature readings as shown in pic when I do the following: using battery power-> connected laptop's power supply -> connected TC4's external power supply -> disconnect TC4's external power supply -> disconnect laptop's power supply



Thanks!

Peter

JimG wrote:
Hi, Peter -

Yes, the Arduino boards have some circuitry to automatically select external power when both USB power and external power are detected. So as long as everything works like it is designed, there shouldn't be a problem on that end.

When I suggest using only one power source at a time, I am mostly concerned about the possibility of creating more ground loops.

Is your laptop charger grounded, BTW?

Jim

petershek wrote:
This raised another question, why there's a temperature reading when the thermocouples were disconnected from the TC4? And am I right on the assumption that when thermocouple is not connected, the reading shown on that port would be room temperature?

UNM wrote:
Well, have done a few roasts with the arduino/TC4/aBourbon. Mostly OK, though last time it hung several times during the roast (LCD still displayed, but no updates). reset brought it back.

if( NCHAN == 1 ) { // dummy values for T2 and RoR2 to avoid confusing pBourbon
Serial.print(", ");
Serial.print( 0.0, 1 );
Serial.print(", ");
Serial.print( 0.0 , 1 );
};

UNM wrote:
Well, have done a few roasts with the arduino/TC4/aBourbon. Mostly OK, though last time it hung several times during the roast (LCD still displayed, but no updates). reset brought it back.

UNM wrote:
Just tried to get pBourbon working - no luck yet. I'm using an ancient laptop with ubuntu 10.04.1. processing 1.5.1.

Bhante wrote:
I've also been struggling with a similar problem with aCatuai ever since version 1.1 was released. However I made a number of changes of my own, and I haven't had the time to check rigorously the exact source. I also went back to version 1.0 of aCatuai since I was also having a number of other problems with 1.1, but unfortunately I borrowed a few lines of code (the new PWM and thermocouple libraries) from 1.1 before realising that it still had the serial port error. Here is some typical output from Processing when the Arduino hangs (LOOPTIME 750, NCHAN 1, MIN_DELAY 300):

Bhante wrote:
I was reducing NCHAN to 1 and reducing LOOPTIME accordingly. I also tried reducing MIN_DELAY to 270-280, but that was not the cause (whether it was a contributory factor I cannot yet rule out, but I think not). Crucial was LOOPTIME - if this was less than 1000 (even 750 with NCHAN 1 and MIN_DELAY 300) it would crash (eventually - after around 7-10 minutes, sooner with other values) with a serial port error as shown. Without the new libraries I think I reduced LOOPTIME successfully, but I need to go back and double check because the serial error sometimes only hits in after a lengthy delay and I didn't do any roasts with this setting at that time. However in any case whether or not it has anything to do with the new libraries, I am surprised that it does not allow LOOPTIME to be reduced when NCHAN is 1 - it looks like it is expecting a 1000ms loop somewhere - in the temperature measurement cyle perhaps? I haven't found anything so far.

Bhante wrote:
By the way I found that when NCHAN is reduced to 1 in aCatuai, pBourbon does not correctly parse the serial data, although the column headings are given correctly at the start of the serial output received by Processing. Does pBourbon not check the number of columns output? A workaround is to put an extra if statement in Logger to add dummy values to the serial stream:


(Note the space after the comma in Serial.print(", "); - it makes the output a lot easier to read!)