Level Shifting and Tablet Building …

circuitfloor1Figure 1: The new tablet uses re-purposed materials on the circuit board floor.

This project is more involved than a simple exercise in converting 3.3 and 1.8 volt logic levels.  It also involves building yet another homemade tablet.  I have four of them now (2 Pi2’s, a C1, and a C1+).  The fifth one (being this XU4) will be the most powerful of the bunch.  So, in figure two we can see I’m beginning to lay out the new tablet…

Read More

Homebrewing a Board for the MCP3426 ADC

circuit3426-g-ccoolleerr2

Figure 1The simple connection from the USBIO to the ADC

The ADC devices currently in all three of my “homemade” tablets are a little under powered, so we’re upgrading all of them to use 16 bit Microchip MCP3426 ADC chips. The smallest reasonably hand solderable chip package is the SOIC. Most of the newest, fastest most glam chips are not even available with old-time DIP packages anymore. This is seriously bad news for oldish guys like myself.

Read More …

A Digital Compass for the Homemade Tablet

compass-adafruitBFigure 1: The digital compass has been mounted in the original homemade tablet, next to the powerful Imedion NiMH “C” cell bank.

The next item to be added to the original homemade tablet was a mims/magnetic compass (purchased from Adafruit at Adafruit.com).  It is an i2c device, so is only a four wire connection (Vcc, Gnd, SCL, and SDA)…

Read More …

A collection of SoC Projects

allmylittledroids7Figure 1: A growing Collection of little Soc/SBC powered computers (click to enlarge).

Today, when I visited my own site, I realized how confusing some of the projects may seem, because they reference different boards and things, and it’s a little bit of a jumble, and it’s hard to tell the players without a program.  Figure 1 should sort out some of the details.  There are two “homemade” tablets and two “homemade” servers at this point, all ARM CPU architecture powered, by SoC based SBC boards.

Read More …

The Homemade Tablet’s Little Brother

serverodroidwithbattery1 Figure 1: We’re growing the family, and HT version two is being born. Here it is shown, perched on top of the original “homemade tablet” (click to enlarge).

Originally, the idea was to put a very small display on the panel of this Hammond aluminum enclosure. I’ve changed plans, and it will just be a server droid.

Read More …