Found a problem with the CRC16 checking of the switch chips. A new version of TeenyPi.ino, TeensyPi Version 0.0.7, 05/04/2013, is up at my github site .
I'm sure that this won't be the last one.
Is the TeensyPiPID.ino OK?
Found a problem with the CRC16 checking of the switch chips. A new version of TeenyPi.ino, TeensyPi Version 0.0.7, 05/04/2013, is up at my github site .
I'm sure that this won't be the last one.
Is the TeensyPiPID.ino OK?
I didn't look at the library for that chip, but I'm sure that the setup would be similar.
Here are the I2C RGB LCD boards that I designed:
The upper board is the current iteration.
They are compatible with the Adafruit I2C RGB LCD boards, but can also be expanded to include up to eight of the LCDs on the I2C bus.
The software I've written will support either the RGB LCDs or the standard HD44780 LCD.
More info at my web site.
What are the power selector and switch jumpers called. Looked for them at Radio Shack and Mouser.com but no luck so I suspect I just don't know what to ask for.
I've seen them called jumpers or shorting blocks.
If you have no plans to change the address or power selection you can also just solder in a jumper instead of using the posts.
So are the posts just header pins, like the header pin strip at the top of the board/picture? I'm assuming, if I am using the TeensyPi software as is, that I would need to change the address if I wanted to use more than one LCD at a time, correct?
BTW, my switchboards are in/populate and seem to be working great! LCD boards are in and the Adafruit LCD/chip should be here Friday. I'll have extras of the LCD boards if anyone is interested.
Great work here, and at your TeensiPi website! Most of your boards have been labeled with the components, bu do you have a list of components for the Adafruit Pi plate replacement board you created? Thanks.
Yes, That's the one. What is the advantage of using 3v3 to 5v level-shifter circuits rather than the 3v3 regulator? I am waiting for that board to arrive to start playing, rather than soldering wires on to the Adafruit Pi Plate board.
Another noobie questions Jimmayhugh:
Does the LCD board connect to the IC2 of the Teensy or the RPI? I expected they would be the same but my TeensyPi board has terminal blocks for both. I'm guessing RPI as I think you mentioned previously that the RPI is managing the data communications while the Teensy is controlling the actions. I haven't found the specific code that tells the LCD what to display; where should I look?
jimmayhugh said:The LCD board(s) are connected to the RPi I2C terminals. The program that controls the LCD board(s) is the compiled program i2c_lcd located at /var/www/htdocs in the latest RPi image (Version 0.0.19 - 04/07/2013), while the c code and compiler script are at /home/teensypi/i2c_lcd/. It uses the WiringPi library, which is also installed.
The i2c_lcd program is in turn started and stopped when an action set is enabled with a LCD selection.
You can also test for the board(s) using i2cdetect.
That helped. I updated the image and then downloaded the WiringPi Library and it lit right up and displayed action status. I populated all the resistors but wondering now if I need the two you omitted given I'm using your TeensyPi board. It works with them...
Doesn't appear that the software is capable of reporting PID status, correct? I don't see an option to tie PID status to an LCD and setting up a parallel Action will report the temp probe but not the PID switch actions or the setpoint.
Jim,
Ive been following your project and really love what you have accomplished so far...
only features missing for me is a way to send a email if the parameters are above or below the set threshold so it can be dealt with if im not at home to keep a eye on the webpage.
other one is a way to deal with a power outage at my house. i have a APC UPS that will drive the rpi and assorted sensors... and to have it send a email to my phone so im aware of the power outage.
whats the chance of adding these options to the webpage? and to the underlying OS.
of note. Ive been around Unix OS's for long time. ever since the days of SunOS 4.0.x and Solaris 2.1 and FreeBSD 2.x and Linux 0.x... i have VERY little experience with embedded.
kladue said:Jimmy, have you looked at the Linear LTC2495 ?, it offers the same capabilities with 16 channels and I2C IO. It includes an on board temp sensor for cold junction, programmable gains, and addressing for multiple units. It looks like a bit of math is needed to convert thermocouple raw values to a real world temperature values.
...The main advantage to using thermocouples is the much wider temperature range available of thermocouple vs the DS18B20...
I don't really understand how in the application this would be applied to on here (temps generally from 0-100°C) a thermocouples range would be an advantage over the DS18B20?
I don't really understand how in the application this would be applied to on here (temps generally from 0-100°C) a thermocouples range would be an advantage over the DS18B20?
According to maxim, the standard sensor has an operating temperature range of -55°C to +125°C and is accurate to ±0.5°C over the range of -10°C to +85°C. I think the advantage of adding a thermocouple would be accuracy for brewing applications where it gets above 85c. Ie brew day.
Jimmy's system could handle a brew from grain to glass.
Others have expressed an interest in using the TeensyPi for other than brewing applications, like smoking meats, which requires a wider temperature range.
So, with all that said, the question becomes: Is there sufficient interest in this endeavor for me to continue investigating the possibilty of using either of these devices?
Maxim just announced the MAX31850 1-wire thermocouple converter. More on this after I get some samples.
UPDATE: There's currently a 17-week lead time on purchases from distributors, so it may be a while before this becomes a valid option.
Jim great work! I just got mine up and running and was wondering if there is a easy way to change the temp to be displayed in Celsius?
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