My Pi

My Pi is a version 2. I hadn't had the need to closely look at a circuit board in a number of years so I was astounded to see the small size of some of the surface mounted components (resistors, capacitors, diodes, and leds).  In my day of PC board design, the smallest resistors I delt with were 1mm and 2mm long.  Now I see there are resistors as small as .4mm long.  Wow!  I can remove and replace the 2mm resisters and possibly the 1mm ones, but the .4mm resistors - forgetaboutit.  You need a microscope. You'll see in a later post where I added 24 of the 2mm resistors to my Gert board.

For wireless, I have an Edinax EW-7811Un, USB, WiFi adapter. As you can see from the photo above, this 802.11b/g/n adapter is tiny.  It works great.  As far as I know, I have never had a dropout.  The photo in the title above was taken outside of my house (for the even lighting) and a fair distance from my router - and the Pi is up and running. 

I don't have room for a monitor and keyboard fior the Pi so I use TinyVPN for communications between my desktop and the Pi. I'm surprised how well it works. I could not have set this up without my son's help. I use putty/pscp SSH for copying files between the Pi and the desktop. My Linux distribution is Occidentals V.0.2.

I have another SD card with XBMC loaded. I connect to the TV via the HDMI port.  I use xbmcRemote app to control the Pi. I guess I'm not the most patient guy around, because I found the speed of the XBMC file access to be frustratingly slow.  I did see a few old Star Trek programs but haven't used it since.

I'll report on other hardware and software I have for the Pi in future blogs.

How I Got Started With The Raspberry Pi

Back in the late 1970’s I introduced my son to microcomputers.  I purchased the Heathkit ET-3400 microprocessor trainer with its hexadecimal keyboard for input; six, 7 segment LED displays for output; and 1K byte of RAM. It was bought as a kit, so half the fun was the assembly.  We programmed in Motorola 6800 machine code.  There was no assembler for this machine.  What fun inserting a line of code. Our most ambitious project was programming the game of Mastermind^®.  Next came the Timex Sinclair where each key had four functions.  This Zilog, Z80 based device came loaded with basic, but it was possible to program in assembly language.  That tiny computer eventually became tricked out with a large case containing the PCB, standard keyboard, power supply, expanded memory, and an expansion port that allowed us to plug in breadboarded circuits.  Among the most interesting circuits we built were a speech synthesizer and tone a generator.  Finally, there was the infamous Commodore 64.  The fun here was building and controlling sprites using 6502 assembly language.

Then came the PC!!! About the same time my son went off to college to become a physicist.  For the next 30 years or so, I did not build any computer hardware, and, virtually, did no serious programming. I  did manage to study C and C++ along the way.  In the meantime, my son became a way-over-the-top programmer on the way to his PhD.

Last summer, he brought his Raspberry Pi on a visit.   After showing me what it could do, it just brought back memories of those days when you could actually control a computer.  There is one big difference though: our roles are now reversed – he’s the teacher/expert and I’m the student.  I immediately bought a Pi with enough accessories to make it work. His interest in the Pi has been in home automation.  He has a very interesting blog that you can view here: A Pi In The House. Of particular interest is use of the internet to monitor sensors, and his use of the Pi's watchdog timer to handle electrical service interruptions.

Before the Pi I had a casual knowledge of Unux and had never written a Python program.  So, I'm really starting from scratch.