Shared Projects

V2 Update to the Original I2C Character Display CPU Board. Identical to the I2C Character Display CPU V2 but with a reversed connector for the display. This is designed for OLED display modules that generally have their connector on the top edge of the PCB, whereas the original non-reversed version is for the ones with the connector on the side edge of the PCB. Otherwise, the two circuits are identical.

See the new I2C Character Display V3 board for a version with a higher powered MCU and better overall performance.

V2 Update to the Original I2C Character Display CPU Board. This board goes inline between a host CPU and an OLED (or similar) I2C/SPI graphical display. Its purpose is to convert the graphical display into a character-based display, removing the overhead of font rendering and pixel transfer over the slow I2C bus from the host.

Note that the CPU here is the ATmega328PB (PB version) with dual I2C ports. 12 MHz was chosen for the ceramic resonator, instead of 16MHz or 20 MHz, so that it will run at 3.3v within the specs given in the datasheet. You may, however, be able to overclock it successfully, especially if running at 5v. Be careful, however, of OLED displays with very noisy voltage inverters, as they will interfere with CPU overclocking. I managed to brick two ATmega328PB CPUs trying to run one with this board at 20MHz. 16MHz, however, was no problem.

An identical board with a reversed display connector is also available.

V2 Additions/Changes:

• Support for SPI communications with the display in addition to I2C

• Support for CPU Driven Reset Line to the display

• Support for either display driven or CPU driven I2C address (DC pin) option

• Ferrite bead on display power to reduce noise from the display’s power inverter

See also the Updated V2 version of this board which provides SPI display mode support as well.

Identical to the I2C Character Display CPU V1 but with a reversed connector for the display. This is designed for OLED display modules that generally have their connector on the top edge of the PCB, whereas the original non-reversed version is for the ones with the connector on the side edge of the PCB. Otherwise, the two circuits are identical.

ND6T AGC design for the uBITX as kitted by K5BCQ. http://www.nd6t.com/uBITX/AGCkit.htm

Eurorack mixer module - front panel PCB version 1.0.1

Holes only. No tracks, no pads.

Eurorack mixer module - controls PCB version 1.0.1

Eurorack mixer module - main PCB version 1.0.1

tandy.wiki/Teeprom

28C256 re-writable EEPROM module to fit into the Molex 78805 socket with non-standard pinout in TRS-80 Model 100, 102, and 200

For Trainer project. This is an Arduino Uno Shield that allows both an Arduino Uno and an Adafruit Trinket M0 control a peristaltic pump.

Power supply bypass and low pass filter for Sharp GP2Y0A41SK0F analog optical distance sensor. Recommended values are C1,C2: 10uf; R1: 160 ohms.

• The board is short in the front to help the port stick through thicker plastic.
• There are resistor pads on both sides of the PCB to allow you to move them out of the way if need be

A basic three-channel NeoPixel controller meant to be used with the WLED project. With 74AHCT125 level shifter, relay for LED power and support for either ESP8266 or ESP32 “D1 Mini” type devboards.

tandy.wiki/Meeprom

28C256 re-writable EEPROM module to fit into Molex 78805 sockets that expect a 27C256 UV/OTP EPROM DIP chip.

TANDY Model 600
Epson PX-4 PX-8

A handheld game that displays logic mazes you have to solve by pressing the buttons.

For more information see: http://www.technoblogy.com/show?45JT.