system information external LCD

[sebo]

I'm sure I am not the first to do this, so there surely there are others here ;)
I built a custom case for the FreeNAS server and I want to attach an external LCD to show system information. i got the LCD and a serial board, but after a bit of inspecting, the 4-pin serial module output seems to be for Arduino.. I thought I could use USB on it.

So, I am trying to find out if i can somehow make use of this module, because I like how on the module, it has a potentiometer for display contrast and jumper pin to turn the backlight on/off.

Trying to keep things simple.. any ideas what I could use? Would this work? Or this one?

What I have:
http://i.imgur.com/X06kHwk.jpg

 

[pirateghost]

That's an i2c connection. You will need a way to interface with the i2c. You won't find that on 99.99999% of motherboards out there.

Now, you could use that with a pi or an Arduino/esp8266 and come up with some stats by using API calls or responses from an SSH session to the FreeNAS.

 

[sebo]

Yeah, it is..
If the FreeNAS server had a parallel port I wouldn't even need the module as the LCD can connect to a display port directly by just soldering to a display serial cable.

Looks l like i just need to get a serial to USB cable, but I'm not 100% sure: https://www.adafruit.com/product/954
I would plug that into the 4 pins off the i2c module.. at least that is my thinking.

 

[pirateghost]

yeah, it is..
if the freenas server had a parallel port i wouldn't even need the module as the LCD can connect to a display port directly by just soldering to a display serial cable..

looks l like i just need to get a serial to usb cable, but im not 100% sure: https://www.adafruit.com/product/954
i would plug that into the 4 pins off the i2c module.. at least that is my thinking.

FTDI is not the same thing as i2c. It isn't as simple as that. I use these same LCD screens on esp8266/Arduino projects. It isn't just a serial connection.

http://forum.arduino.cc/index.php?topic=69257.0

https://en.wikipedia.org/wiki/I²C

https://en.wikipedia.org/wiki/FTDI

What you are asking to do will not work. If you got anything from it, it will be garbled data, and it is doubtful that FreeNAS would support it (drivers/python dependencies/c++ dependencies, etc)

 

[sebo]

I just have to find the right module. Take a look at:
http://www.lcdmodkit.com/lcd/U204GMB-B1.html

And one guy here managed to make his own USB adapter for a pc/server build.

Just found this: http://www.tldp.org/LDP/LG/issue77/taneja.html

LCDproc should also work on FreeNAS with a little tinkering.

Now off to find some LCD 2 USB module..

Cheers.

 

[pirateghost]

I've used lcdproc on other projects. You're assuming that it will "just work" with FreeNAS but it is highly unlikely that you will get it working without messing around with FreeNAS, which is bad.

 

[wblock]

How do we know that's I2C? There are PIC-based serial to LCD adapters that are very similar to that. Just get one of those. A USB-to-serial adapter will work with that, although you need to be aware of the voltage needed. I've used CH340, PL2303, and the... other one I can't recall. I've even used the FTDI ones, but do not recommend them due to their attitude problem.

And then you could also just use an Arduino as a driver board for the LCD. That will require a bit of programming.

 

[pirateghost]

How do we know that's I2C?

Aside from him admitting it is?

Or maybe from the pic?

Or maybe because it's like one of these?

 

[wblock]

Here is a serial driver board: https://www.sparkfun.com/products/258. It's only 5V serial, though, so would need also need a 5V USB to serial adapters.

 

[pirateghost]

Here is a serial driver board: https://www.sparkfun.com/products/258. It's only 5V serial, though, so would need also need a 5V USB to serial adapters.

and then how do we interface with FreeNAS with it? a jail with lcdproc installed? what data will be fed to it?

 

[wblock]

It's serial ASCII. I would aggregate the information desired (probably from top or systat, excerpts of log files, maybe sensor temperatures from ipmitool) with Perl or a shell script, then just dump it out to that device, /dev/cuaU0. I wouldn't expect it to accept VT100/ANSI control codes, but it might. There should be screen-clearing and cursor movement commands also.

 

[pirateghost]

I have doubts that you will be able to just shoot it the strings and have it display them.

Just dumping to the device does not format it correctly or put it on the correct lines. There is a reason there are libraries and daemons that handle this stuff.

 

[wblock]

That is the point of the serial ASCII board. Send serial (RS232) ASCII data into that, and it controls the parallel interface of a standard character LCD. I think $16.95 is overpriced for that board or I'd buy one and prove it to you. They have a tutorial that says "send text to the display through your serial port": https://www.sparkfun.com/tutorials/246

It's essentially a receive-only serial terminal with a really small screen.

Again, this could be done with an Arduino. There is probably code out there already, come to think of it.

 

[pirateghost]

Again, this could be done with an Arduino.

That was my point in the beginning. I2C works just fine with Arduino. I have set up several of these LCD screens with Arduino and ESP8266 chips.

A Raspberry Pi Zero attached to this display over i2c, sending data across FTDI/Serial from USB would work just fine too.

My preference would actually be just a plain wemos D1 mini, connected to the display and write a python script that sends messages to mqtt with the data, and have the wemos d1 mini grab the data from MQTT topics and display the data.

EDIT: Hell, if the OP wants, I would be happy to even write the code for the wemos d1 mini, as I have plenty to play with here.

 

[BloodyIron]

So... did any of you folks get an LCD screen working showing IP address or whatever?