Deadlines are looming and Cthulhu, our Camjam’s Pi-Wars Challenge robot has come a long way since the prototype emerged earlier in the year. (See Israel’s blog here.) The Team comprises a mix of techies from the youngest, James to me – I refuse to acknowledge to being the oldest! Tinkering, adjusting and modifying our prototype is more easily done by two – or at the most – three team members at a time, so Israel lent Marian an HC-SR04distance sensor to “play with” and work out the coding. Now Marian goes to a school that seriously believes its pupils’ spare time must be filled with homework to the exclusion of all else, but at the weekend we found a mutually convenient time and settled down to some coding. “Modmypi” had a tutorial, here, that we could follow. Easy! What did we need? Ah yes; a Raspberry Pi; the HC-SR04, a breadboard, jump leads and two resistors.
First snag: I have forgotten most of my Physics and Marian has not yet studied the subject. So we carefully read how a 1KΩ resistor was to be used in series with a 2 KΩ resistor to reduce the 5V input from the distance sensor to the 3.3 V that was the maximum for the RPi. Yes, I think we’ve got that. Oh! There are so many pretty striped resistors in the box but which one is the size we require? Memo to self: consult Ed at SoSLUG for quick lesson in resistors. We consulted “Google” and identified a 1 KΩ resistor. “We could use two 1 KΩ ones together to replace the 2 KΩ ,” suggested Marian. And we returned to the tutorial. Well: I did. It was my task to download the code from the tutorial onto my RPi while Marian continued to build our own line sensing robotic mouse from a commercial kit. Snag number two. My RPi was not connecting with the Internet. Oops! The Wi-Fi dongle was missing. Worse still it turned out to be completely lost. In my search for an Ethernet (correct term?!) cable I remembered that my new Pi-Top include a Wi-Fi dongle so I “borrowed” that.
Ta dah! Located the code from Modpypi’s tutorial. Snag number three. I have absolutely no idea how/ where to save it. I simply have not done enough Raspberry Pi-ing on my own. Vague memories of “command line” and “text editor” and use “startx” flitted across my brain. At that moment Marian’s mobile rang. Supper time – she had to go.
Dilemma: do I persist in playing around with my RPI or do I give in to temptation and pick up my needlework? It is a no- brainer! Tomorrow I will sort out my RPi. If all else fails, someone at SoSLUG will guide me!