00:00:28.960
Hello, Ruby! Please join me in welcoming our speaker.
00:00:58.920
Hitoshi Hasumi.
00:01:12.439
Hello! Oh, do you hear me?
00:01:26.079
Okay, uh, hello! You're very lucky.
00:01:31.400
You chose my talk. I think there are a lot of talks that are difficult today, right? You look tired. My talk is very easy, so be relaxed.
00:01:40.040
So let's start! Oh, I think I still have one preparation. Wait a minute.
00:02:28.840
Hello! The title of my talk is "P Ruby Episode Four: The Rise of Microcontroller Ruby." Actually, this is episode four.
00:02:35.400
Former talks included episode two, "Attack of the Rake," and episode three, "Revenge of the Standard Interface." This year, a beginner's complete guide to microcontroller programming with Ruby can be found on the internet, please check it later.
00:02:48.319
And episode one is "Hidden Story." It's not published yet.
00:03:03.799
Let me introduce myself. My name is Hitoshi Hasumi. Hasumi is my family name, and Hitoshi is my first name. So you can call me just Hoshi or Hasumi, or whatever is still okay.
00:03:18.040
It's my internet name on GitHub and Twitter. I am the creator of P Ruby, which I will talk about today.
00:03:30.360
I also created PK firmware, which is keyboard firmware written in Ruby. Actually, this keyboard runs with Ruby now.
00:03:43.799
I am a committer on the series IRB, and at the end of this year, 10 days from now, RCC will be shipped with a new IRB that has been greatly improved.
00:03:50.000
So please take a look at the new IRB with R3.3. Actually, here’s another IRB maintainer out there. Please ask her, not me, about IRB.
00:04:04.439
I am a two-time first prize winner of the Ruby Award. I was also a finalist for the Ruby Prize two years ago because of P Ruby.
00:04:12.040
Can I ask something? If possible, please turn off your Bluetooth because I'll show you a Bluetooth application during a demonstration.
00:04:18.799
The number of the Bluetooth channel is, I think, 12. It will become very congested easily, so just turn off your Bluetooth for my talk. Let's begin with microcontroller programming with Ruby.
00:05:06.759
Connect your Raspberry Pi Pico W and laptop while pressing the boot select button. You'll find the RP2 drive in the file manager. Connect and download the "RP2.uf2" file from GitHub or release. It's an executable file out there.
00:05:38.199
Then just drag it into the RP2 drive. You can find a screen that looks like this. Let me try. Here comes P Ruby! This is the first screen. This is the hardest thing about my talk: every computing resource is in the Raspberry Pi Pico.
00:06:30.360
This screen was created by the Raspberry Pi Pico, not my laptop. Is it okay? Then this looks kind of unique, like a shell. You can type some command like 'L'. There's no file, 'PWD.' Oh, now I mean at home. 'LS' shows things like 'beep.' There are some executables. Maybe we can use 'date' command.
00:07:07.600
Yeah, you can see the current time. The Raspberry Pi Pico doesn't have a battery to keep the current time of a real-time clock, so every time you start it, the time should revert back to the epoch time. But you can process the current time using a battery if you want.
00:08:02.000
This means Ruby itself running on a microcontroller. Furthermore, Ruby can be compiled into VM code on the fly. You have to understand this! This means there is a small footprint Ruby that passes on the microcontroller.
00:08:59.440
By the way, RP2 stands for Ruby own Raspberry Pi. That's why I named it RP2. I would love to move such kind of robot with Ruby in the future, but not for today.
00:09:46.320
This is today's setup: two Raspberry Pi Pico W here, a character display, and some FTDI USB TTL serial converter cable. This is the setup for today.
00:10:13.840
About the Raspberry Pi Pico, there are two types: one with Wi-Fi and one without. The type with Wi-Fi has BLE (Bluetooth Low Energy) and Wi-Fi features. Today, I'll show you the BLE feature.
00:11:08.480
This is the very beginning of microcontroller programming. GPIO, let me do it. CYW43 is a wireless module.
00:12:11.440
Oh, I should have required 'CYW43' and 'CYW.' If I write 'gp.WR1,' what’s going to happen? Guess what is going to happen! Yes, it turns on the light. To turn it off, write 'GP.0.' You can do things like that.
00:13:09.440
You can incrementally try out the GPIO and see how it works. Now, let’s make an LED.
00:14:01.920
This will look like this. Actually, let me use a has method. How does the 'own method' look like? 'GP.1' - if you want the LED to turn on, then 'LED#on.' Really? What about though? Are you a copilot and one more thing, invert it.
00:15:40.640
If you achieve this, please pray for me. This is a kind of VI editor. How can I save this file and exit the editor? How can I say 'wq'?
00:16:29.040
I require 'LED = LED.new.' If I hit 'LED.invert,' it turns off.
00:17:18.000
Yes, right! And if I...
00:17:48.319
Oh yes, something’s wrong. But don't mind, let’s go to the next example.
00:18:49.440
GPIO is the most basic peripheral of microcontrollers. These three peripherals are more complex, including serial communication protocols, I2C, SPI, and UART.
00:19:23.760
Writing an LED class means creating a kind of device driver. The LED class and GPIO class provide basic low-level function.
00:20:56.800
The same can be done with the LED class. Just like that! It was a piece of cake.
00:21:54.720
But as we will see from now, wrapping SPI and I2C is much more valuable than LED.
00:22:35.600
This is very long to type for me, so I will cheat a little.
00:23:34.800
Oops! Some things are going wrong.
00:23:54.720
Oh, it doesn't work today. Oh, I'm sorry. I made a mistake. This should be the one, because I2C is...
00:24:36.400
These are just initialization procedures. Don't mind the details.
00:25:03.440
I'm ready! Who sees the camera?
00:25:29.680
Something went wrong - wait a minute, we have enough time.
00:26:30.160
Okay, the connection was loose.
00:26:56.000
Just, I mean, a kind of mistake but let's go and move on.
00:27:02.000
This is very long to type, right? Maybe because I made a mistake, so this should not work.
00:27:46.400
But it's okay! It seems we have a better one.
00:28:07.520
This already has the LCD RB.
00:28:25.840
The LCD class looks like this. It's not so complicated, right? But you can already be familiar with the reset method that I showed you just before.
00:29:21.920
The usage of the LCD class looks like this: 'LCD.new.' See? Initialize it, then just 'PR hello.' You can see... 'LCD' with a break line.
00:30:07.680
Let's see if this works.
00:30:55.520
In this way, we can write our own device driver incrementally with IRB. This is a kind of cool experience, right? This is microcontroller programming!
00:31:36.520
You don't need to write C; I've already done a lot of C for you, so you should just write Ruby to handle the hardware.
00:32:25.760
Unfortunately, we don't have enough time, so I will skip the SPI class that uses the thermometer. I will show you the final project.
00:33:40.000
Today, I copied the main.rb. If the main.rb file exists, that file will run at startup. So just reset the microcontroller to start the app.
00:34:18.000
You don’t need shell command anymore. Detach the cable and just connect it again.
00:34:51.360
But it doesn't work.
00:35:18.880
Sorry, I made another mistake; this should be 'broadcast.'
00:35:40.000
This is now battery-driven, a standalone IoT product! If I switch this on...
00:36:48.560
The live demonstration is very difficult!
00:37:30.560
This is now reporting the temperature of the room through Bluetooth!
00:38:49.680
Observer devices are working to catch the radio waves from this device. If everything goes correctly, this will show the temperature data.
00:39:43.520
In this way, we can create real Bluetooth applications with Ruby.
00:40:07.680
What I wanted to talk about today is a Ruby implementation targeting microcontrollers and building device drivers for general I/O like GPIO, TCP, and PWM.
00:40:35.480
They are ready, and you can incrementally write your device drivers and applications with P Ruby. The BLE is also ready but still unstable for real applications.
00:41:28.240
So, you can make an IoT system with Ruby. That's all for today! Please scan this QR code and visit my repository at GitHub.com/P/P-Ruby.
00:42:25.440
Thank you all! Okay, thank you, Hitoshi, for your informative sharing. Now, we have no time for a Q&A session, but if anyone has questions, please raise your hand.
00:43:02.920
Now let's end this meeting. This meeting is adjourned.
00:43:12.920
Before you go, if you want to attend the AAL party, please raise your hand. About 80% of people. The official party will commence at 6:00 p.m. at the P College office.
00:43:27.680
The topic of the panel discussion will be 'The Future of Engineers' Happiness in the Age of AI.' We welcome everyone to attend and remember to bring your ticket.
00:43:46.880
Lastly, check in at the reception tomorrow to receive lunch boxes. If you find any lost items, please bring them to reception. Thank you!
