My DigiKey order arrived Friday. Woo hoo! I ordered the wrong 28 pin sockets (too wide) but I can cut them to work with the ATmega8 chips.

Saturday I built the frame for the 8 bit switch bank. I like the way it looks. I'm sure I won't do too many full-length programs with the switches, but they will be fun to play around with. I will add some startup code to the project to read the switchbank. Then the device can do different things depending on how you start it up. A more Altair-like mode is definitely in the works, so you can enter simple programs direct to the Mega8 and then execute them. A variety of blinkenlights modes are also planned.

Maybe I'll build a series of these things and give them to my geek friends. I'd also consider a 8x8 LED display panel, if I can just figure out how to connect it. I guess I could use a decade counter to run the row select, and an octal buffer as the column driver. 9 pins to run the whole thing, so an ATtiny2313 should drive it just fine. Low-res voltmeter anyone?

Bought the 8 bit switch bank today ($4.80 for 10 switches), along with some 14 guage wire. Way overkill but whatever...

Sad 'cause sparkfun is down today. I'd like to get the ethernet breakout, and a few other things. I'll probably put in a Digikey order also, but getting the right parts from Digikey is a real chore. They have so much stuff! Looked for the octal buffers at RShack, no luck there. All they had was op-amps and 556 dual timers.

Still haven't decided if I will write the software for WOSP in C or ASM. Either would work fine. I'll try the switches out tonight. I'm sure the Arduino pinout diagram will come in handy.

Or, a new take on the Altair.

WOSP provides a way to create and edit programs in Atmel AVR microcontrollers at the byte level. The programmer provides a bank of 8 data switches for program input. Output consists of 12 address lines and 8 data lines. As the AVR uses word-based program memory the programmer shows one byte at a time, allowing you to switch between High and Low bytes.

The basic programming model is to set the switch bank, set the High/Low byte switch, then press the 'Write' key. Pressing the 'Up' button advances the address pointer to the next address. The 'Down' button allows movement backwards. Once the program is complete press the 'Store' button to send it to the microcontroller. You can also use the 'Load' button to read the microcontroller program into the editor.

A 'Goto' button allows you to enter a new address directly using the switch bank.

Implementation: The core of the WOS Programmer is an Arduino board running a simple program. The program defines a 512 byte data area for the target program. Input and output use 8 bit data latches and a common data bus (on the Arduino Port B).

There is also provision for uploading the target program from a host PC to save all the switch flipping.