An interesting project which mashes a Pi, a battery, an ADC and a sensor together to create a standalone gas sensing gadget.
Getting started with Databases on the Pi with SQLite (reblog)
An excellent step-by-step blog post about installing and using SQLite. Further blog posts will cover how to use the database in PHP. I’ll be keeping an eye on this in my quest to learn my way around PHP!
An Unofficial Raspberry Pi Blog: Getting started with Databases on the Pi with SQLite.
I just won a Dreamer Nano!
I just won a Dreamer Nano v4.0 over at Will Garrido’s blog MobileWill! (And I never win _anything_! The last thing I won was a Space LEGO set back in the 1980s!)
The Dreamer Nano V4.0 is a surface mount breadboard embedded version of the ATMEGA 32U4 with integrated Micro USB. It has everything that Arduino Leonardo has (electrically).Physically, it is just missing power jack to save space.
Using the ATmega32U4 as its sole microcontroller allows it to be cheaper and simpler. Also, because the 32U4 is handling the USB directly, code libraries are available which allow the board to emulate a computer keyboard, mouse, and more using the USB-HID protocol!
The Dreamer Nano v4.0 is compatible with most Nano shield in the market. It’s suitable for projects that require a compact size controller system.
Specifications
- Microcontroller:ATmega32u4
- Operating Voltage:5V
- Input Voltage (recommended):6.5-12v (VIN) / 5v (Micro USB)
- Input Voltage (limits):6.5-12V
- Digital I/O Pins:20
- PWM Channels:7
- Analog Input Channels:12
- DC Current per I/O Pin:40 mA
- DC Current for 3.3V Pin:50 mA
- Flash Memory:32 KB (ATmega32u4) of which 4 KB used by bootloader
- SRAM:2.5 KB (ATmega32u4)
- EEPROM:1 KB (ATmega32u4)
- Clock Speed:16 MHz
- Compatible with most of Nano shield
- Size: 45x20x20mm
This was the original competition post and this: MobileWill: 100th Post: Giveaway Winner! is the follow-up winning announcement.
Need to work out how to get it working with the Pi now… think through an Arduino would be the best bet. It is, of course, breadboard mountable, so I’ll investigate the pin-out when it arrives and see what I can do direct from the Pi.
Summer Coding Contest results
I don’t normally publicise a blog post by the RP Foundation (they do well enough without me!) but I felt that this was one of those times!
The results for the Summer Coding Contest have been announced and have made the news on the BBC News website!
Some fantastic project ideas on here, so well worth reading!
Minecraft: Raspberry Pi edition announced
Minecraft will soon be coming to the Pi! For more info (though not much yet!) see the official Minecraft announcement.
Login terminal over USB/serial link to Jornada 680
The aim
To operate the Raspberry Pi using a Jornada 680 (pictured, left) as a dumb terminal.
The solution
The Jornada 680 has a cable for sync-ing to Windows, the end of which terminates with a serial connector. Now, as we know, the Pi does not have a serial port exactly (although, you can create one by using a GPIO to USB cable and then a bespoke connnector) but it does have USB ports, of course. Having briefly toyed with the idea of building the connector, I decided eventually that a serial-to-usb cable from Maplin would be the easiest (if not the most fun) solution.
So, I now had the following:
Jornada 680
to
Jornada sync cable
to
Serial-to-USB cable
to
Raspberry Pi.
The next step was to get the Pi to present a TTY session (Terminal session, login prompt, whatever you like to call it) on the USB port. Remember, we want it on the USB port not any serial port. As far as the Pi is concerned, it’s communicating with the Jornada over USB.
I looked at using Minicom to set this up before eventually finding information on just setting up ‘getty’ to give a terminal on a particular device.
To do this, you just need to run the following command on the Pi:
/sbin/getty -L ttyUSB0 115200 vt100
I put this into a script called usb_tty_start.sh. Now, we want this run automatically. You can’t add it to /etc/inittab (which is where one would want to put it as this is what configures ttys and login prompts etc) as the USB port isn’t ‘up’ before this is run. So, we add it as a command to /etc/rc.local which is run after the USB is ready.
Now to find software to use on the Jornada 680. This device uses the SH3 processor so we need to find software that will run on it.
So, options…
- PockeTTY – it works but is limited to 5 minutes. Very annoying that companies don’t just allow their very very old software to be free!
- zterm also works, but same problem as PockeTTY in that it’s still a paid product.
- vxHpc exactly the same problem, although it is a very nice program.
- Pocket Tera Term works brilliantly and is free.
So, there we have it. Connect it all up, start the tty on USB on the Pi, then run the Terminal emulator on the Jornada 680. Sometimes you have to hit enter a couple of times to get the login prompt up.
I’ll probably add some photos of the set-up later.