well it's time to do some tinkering with this little display that I pulled out of
this remote control in last week's video I've off-camera I soldered some header
pins onto it initially I tried to use the ribbon cable little sort of paper
type ribbon cable that was on here but the pitch was just too narrow to get
onto the header pins so I replaced it with some bits of cat5 wire and here we
have this conveniently hovering above the board got an Arduino Nano here piyo
jumper wires page printed out from the datasheet that I found for this thing
showing the physical connections I've got a similar one in here for reference
another different this is the tool 16 by 2 this guy is 20 by 4 so is this guy and
this one has the its pins labeled and those pins match the piano down here on
these little iqc backpacks which isn't labeled so I've got that for reference I
think later on I'll try this but first I'm gonna try and hook this up just in a
four-bit kind of paralleling mode on the datasheet here
oh this the so we've got ground power negative power supply for the LED or the
low voltage which is for whatever reason just 0.7 above ground interesting that
the data or instruction so that will be high if you're sending you know actual
alphanumeric characters and low if you're sending instructions like clear
the screen move the cursor to hear stuff like that that a read/write selector and
a an enable starts today to rewrite and then we got 8 data bits so you can send
data to it in peril actually a couple of different modes that I found on the
on the datasheet and on in my looking at libraries and stuff you can understand
all eight bits at once or you can just send four bits the high or high ones but
send them twice with I think a read write or some other thing in there I'm
not sure fortunately the libraries take care of
most of that I think but regardless you only have to wire up the top four or
data bits and then all these ones up here so you don't aware of all 14 pins
and the 14 pins is what this guy is the rest of these ones use 16 pins which is
among the reasons why I can't put that backpack straight on there the other
reason is of course that the pin spacing is different so that's why I didn't just
solder it directly on like this when he soldered on I'm gonna go with just
direct pins on there but initially I'm gonna wire it up just in parallel mode
and I found a library it's the standard liquid-crystal library it's the library
that works with these guys that they're in one of these Kingdom I in my starter
kit not that one this one which is that your headset up for a long time just as
a temperature thing to play with currently it's got the ITC backpack on
it it came without it so the first time I used it I just use a generic LCD
library and this parallel mode that I'm about to do on this one and it worked
first try so hopefully that'll happen here too I'm just going to speed through
wiring it up basically in the in the liquid crystal library examples there is
a demo called hello world what a shocker and it shows the the pin out on the
arduino based on the sketch so i'll just match that up with what I see in here
and connect them up and I'll be back in a minute
oh yeah I'm probably gonna have a beer or two while I'm doing that there sip or
two of beer tonight it is juicy Oats oatmeal stout from Oxus Brewing Company
in Winnipeg it's one of the few breweries that I haven't visited yet
dark ale with coffee and chocolate notes creamy smooth body next traditional
oatmeal stout
okay that's all hooked up you notice I didn't use those for wool bits on there
as I was discussing so there is the connections that is 10 wires which isn't
that bad this one the third wire is that one that says it's supposed to be a LCD
- and it's supposed to 0.7 volts above ground so I'm thinking that I might just
put a diode in series with that just to give Robbie a 7 volt or point 7 volt
drop across the diode I'm not sure if that'll work or not we'll try it here in
C so what the hello world sketch loaded up on here already you've seen sketches
get loaded so that's not a big hairy deal let's see what happens it says
hello world and it's counting so this is just the standard hello world sketch
that comes with the library and all it does is Chris green put the cursor on
top left print hello world go down and print how many seconds they are doing
has been turned on they hit the reset button it resets that so that is what's
happening there and that is pretty freakin awesome
so that wasn't even all that difficult and a person could stop there if they
wanted to however that's using two three four five six pins of the Arduino if we
use the i2c backpack where did it go
if we use the ITC backpack however it will only take two pins serial clock and
serial data leaving the rest of them no for other things so let's uh give that a
try shall we it is ground that is 5 volts if CL is a
5 and s the a is 84 okay so that's all it takes to hook up the the backpack
now I've just got a hook straight across all 14 pins basically right and I
probably shouldn't need those first four but I'm gonna hook them up anyway it'll
use it or it won't and this is just gonna be exactly the same woman I'm
gonna use a whole bunch of shorter layers here so I think I'll just skip
ahead so you don't have to watch that again okay there it is all wired up and
apologies to the people who are not colorblind true but I decided to use all
the same color wire just just because it doesn't really matter that much they
just go straight across so that's uh yes we need a different sketch we need an
eye to see based sketch now which is from a slightly different library
actually before we get started the first thing to do is detect which I see eye to
see port or actually see address the that backpack is running on so we'll use
this little sketch here is i2c detector sketch and it is telling us that our ITC
board is on address 0 to 7 so now then there's I'm using a library called
liquid crystal eye to see duh what a surprise there
and the wire library which is what you need to run ITC backlight pin doesn't
matter I'm going to change that to two seven if that's what it is and I don't
know what the rest of this does backlight doesn't matter because they
don't actually have a backlight pin 13 isn't connected to anything so it
doesn't really matter so upload that hmm okay that's a problem I'm gonna go off
an experiment for a minute here or two or three I'll be back
okay I think I've got it now I had to mess around a little bit and strip it
back and find some other stuff online anyway this one actually compiles so
let's send it and see what happens okay there we go see that yeah so a
couple of things that I hid to mess around with the softer and libraries was
obviously one of them and that doesn't come as any surprise because I am not
all that comfortable in software world as I'm sure you know if you've been
watching the other thing that I had to do was so on this on the this unit it
seems that it needs the LCD driven differently than this one this one it's
power supply for the LCD I'm pin three needs to be held low and at 0.7 volts
and so previously I just wear that straight into the in through this diode
here this time I've had to do the same thing but all the rest of them are
straight across just ignore that pin on here I'm not sure why maybe it's for a
an LCD that needs a positive voltage there I don't know
what's on that pin penis three I don't short them it's being held at
exactly half of VCC at two and a half volts so obviously that's not going to
work if this thing wants a low voltage something to keep in mind and that took
a fair bit of dicking around with once I got the codes even compile and upload so
here we are and I couldn't be happier I must say now I can put whatever I want
on there 20 wide by 4 high and I'm wondering if it's the same thing on this
one because I remember when I got this one I just tried to play with it quickly
and I couldn't get it to work I did find that it's backpack has a slightly
different ITC address even though it is the same board and it's around here it's
the same board even the address jumpers are all still open so I'm not sure well
the chip looks a little bit different this one's a Philips chip that one
something else maybe that's got something to do with it anyway
regardless something to keep an eye out for and actually yeah maybe I will
oh no I have no way of pulling that to ground on here well yes I could put the
ground through a resistor or something yeah maybe I will try it hang on I'll
just change things up I'll have to change this is the code a little bit to
talk to this one I'll be right back okay I've got this guy connected up and it's
just connected to the backpack right now I've uploaded the same code only with
the ITC address changed to 3f so well let's plug it in and see what happens
Oh actually didn't expect that to work its previously on us messing with us
when it didn't work okay so I guess it's backpack is the correct one for this and
it came with the backpack on and I'm pretty sure so yeah now I have two
working LCD displays Oh
so we've rewritten the code a little bit just to add in a second LCD definition
and put both of the i2c addresses in and since I to see uses same two wires to
connect to multiple devices on the bus just with different addresses I
connected the other both LCDs up so as you can see this one is still running
this one's not showing anything right now except for some blank pixels but
they upload the sketch let's see will it work
that one got cleared
they work so I I made this one a little bit different and push the hello world
over a little bit just so that it wouldn't wouldn't would look different
and you could see that they were different sketches or different texts
but haha and they're both running off that same
pair of pins right there that is slick now I could probably do this with a
bunch more I could probably do that with this as well but in the code I think I
said it's not that much more debate basically just copied everything over
again zero 3f that is the kind of the larger one and two seven is the new one
that I grabbed out of that remote I'm not sure why there's two LCD in its they
were in the example sketch that I copied so I just left them there backlight
shouldn't matter although the kind of orangey one the
larger one Easy's in the backlight so that's fine and then begin a twenty by
four LCD if I was using the smaller one I can make that a sixteen by two and
then I'll see need number one and the same thing again and then down here LCD
set cursor zero zero hello world zero to the time LCD one do exactly the same
thing only space it over a little bit that's fairly slick and I'm actually I'm
pleased that was so relatively easy to do and that I got a free LCD that I can
use that's also pretty cool I'm gonna have to go scouring through the scrap at
work a couple of things somebody on the original video commented that maybe this
is a polarized screen and maybe this is a polarizer I tried it it isn't it's
just clear nothing magic going on there somebody commented that I should try
doing an rs-232 loopback on this and see what happens if I push some buttons
good idea unfortunately they've already cut this apart if I find another one in
the scrap at work well bring it down here and give it a shot just to see what
happens well that was that was a lot of fun um and you can't be angry at two
salvaged parts that work thanks for watching everybody
I do appreciate it um not sure what I'm gonna do next actually no I dunno what
I'm gonna do next week I've got got something that uh that our buddy another
youtuber sent me so I think I'm gonna play with that next week but for this
week that's it comments questions Dumbo as usual thanks
again talk to you later