Totally in the spirit of "How Open Is This Gadget?" the Arduino company also follows the open source philosophy. Over the years, their ecosystem of microcontrollers and accessories has grown steadily and the software has been and is constantly being improved. Microcontrollers are a dime a dozen, but without the appropriate software and documentation, the value of a chip is no higher than the sand from which its basic material, silicon, is extracted. There is plenty of open source hard- and software offered by Arduino, which makes creating projects for "Physical Computing" really fun. I received a package with four different microcontroller boards directly from the company's headquarters. Inside was my favorite microcomputer, the Arduino UNO, and 3 other boards. I like the UNO mainly because of its minimal resources, and for coding there is: less is always easier to understand - the fact that the ATmega chip is removable in version R3, is another big plus. The UNO in the package including a sound kit is the version that has to be populated and soldered before use - Beginners should buy the assembled board. The MEGA is comparable to the UNO in terms of clock frequency, but offers significantly more pins for controlling your own hardware - sometimes 54 pins are better than just 20 pins. The DUE has just as many GPIOs, but its microcontroller is clocked at 84MHz and can therefore perform significantly more arithmetic operations per unit of time. The newest product in the package is the GIGA board, which was freshly launched by Arduino. With a total of 76 input/output pins, this has even more GPIOs than the MEGA and DUE. The built-in microcontroller is an STM32 that has two cores that are clocked at 240 or 480MHz, which again means a significant boost in terms of computing power. What is striking on the board is a USB-A interface, via which the GIGA is not programmed, but which can be used to address peripherals. The round, 3.5mm audio jack in conjunction with two 12-bit digital to analog and two 16-bit analog to digital converters invites you to experiment with speakers and microphones. Also on board are Bluetooth and WLAN, as well as a camera and display interface. That's all about the specs for now, you can read all data on my pages and on those of Arduino. After receiving the GIGA board, I quickly built a few projects in order to test the higher computing power and check some of the new capabilities: With project number 1 I visualize digital signals. An UNO is used as the signal source, which outputs a hardware pulse-width signal on pin 5 with a duty cycle of only 12.75%. The default frequency of the analogWrite() function is 976Hz on this pin. Here I have written a quick & dirty software for the MEGA with which it can record that frequency quite precisely - values between 972 and 976Hz are displayed. If the base frequency of the pulse width signal on the UNO board is increased to 7812Hz... ...and the time base of the MEGA set to the smallest interval,... ...the base frequency of this signal can still be recorded quite accurately. You can read values between the expected 7812 and 7575Hz. Now the base frequency of the UNO is set to 62500Hz. The MEGA is obviously too slow to read that signal. You can see unevenly distributed square pulses and the frequency displayed is clearly wrong at just 31kHz. One of the great advantages of the Arduino ecosystem is that one and the same software can be easily installed on different microcontroller boards. Only the definitions of the pins for controlling the display have to be changed in this chase - all remaining code is left untouched and sent to the GIGA-Board. Thanks to its higher computing power and thus smaller time base, the new family member can record the 62kHz signal quite precisely. With readings between 62500 and 58823Hz, the measured frequency hits the actual frequency on the UNO board. As told before, the software is written Quick & Dirty and so doesn't bring the GIGA to its true limits. I will use this "GPIO sniffer" to visualize the signals on my demo board for a double H-bridge. This freely programmable motor driver is based on an Arduino UNO. Project number two makes use of the analog inputs the GIGA offers - I have connected a microphone to one of them: Since this software was also written on the fly due to a lack of time, I use a normal analog input with a 10-bit converter. As soon as a specified threshold value is exceeded, the recorded sound wave appears on the display. Analog inputs are available in large numbers, so a second microphone can be connected quickly. If there is a suitable distance between the two microphones, the curves show that sound does not propagate at infinite speed. The the sound source can be localized from the different signal propagation times. For the calculations there is: The more measurements can be carried out per unit of time, the more accurate the time difference recording becomes - even simple experiments can benefit from a higher processor clock rate. By locating sound sources, for example, ambient noise can be canceled out - with the appropriate computing power even in real time. Music combines physics, maths and coding in a very vivid way: Building an electronic piano isn't too complicated, and with the on-board audio output it's even easier. Or you can automate a musical instrument like this one: With a plus in GPIOs and computing power that the GIGA offers, further experiments can be carried out with the xylophone. The Arduino GIGA is an intermediate step from the classic microcontroller to a fully-fledged PC. The advantage of the GIGA lies in the fact that the architecture and thus the software required for operation remain reasonably manageable. The experiments shown so far were classic microcontroller tasks that only made use of the GPIOs. Thanks to the diligent programmers working for Arduino, the additional interfaces such as Bluetooth, USB or, as can be seen here, the WLAN interface also work. The connection to the web server is slowed down with delay() statements in order to be able to follow the data transfer process on the small screen. That's all about my first thoughts on the brand new Arduino GIGA board. For more information, visit the "How Open Is This Gadget?" website. And what can be done with microcontrollers, there's plenty of information on my second project: "HomoFaciens". Thanks for watching and: "I'll be back!"
