Friday, June 22, 2012

GMduino II, Arduino Clone with RTC and EEPROM

Project Objective: To design an Arduino clone with through hole parts for easy assembly. The clone also includes an on board real time calendar clock with battery backup and an EEPROM. The board should operate at 5V and 3.3V including the RTC.

  1. Arduino clone with stacking connectors
  2. MCU: ATmega328P with Optiboot
  3. Through hole parts, except for regulators
  4. Serial communication using breakout boards
  5. Dual ldo regulators for 5V and 3.3V
  6. Power :input:  6V to 9V wart or USB jumper selectable
  7. Power switch
  8. Auto reset defeat switch
  9. On board I2C, EEPROM and RTC with battery backup.
  10. Vertical reset and ISP at front
Introduction: The project is an outgrowth of the Rainwater Monitoring System , RMS. The original development was done with the uLab28 PIC, then resulting in the Picduino. The RMS is basically a water tank level data logger with LCD display and keyboard.

Note: Layout complete ready for BatchPCB, GMduino.03C

Under construction

Thursday, June 14, 2012

Daiduino, an Arduino form with the ATmega1284P

Project Objective:
Wouldn't you like to have an Arduino that had 4 times the code capacity, more IO pins and used standard shields, but was only slightly larger? So would I. Further, I would like it to use through hole parts, so that it could be assembled as a kit. By the way, dai is a japanese word that means great or big. So Daiduino is a big Arduino but not a mega Arduino.

I started my Google search, looking at the Sanguino which uses the ATmega644P and has 64k bytes of code space, but soon found the ATmega1284P which has the same pinouts and 128k code space. As a matter of fact the Atmega1284P can be used on the Sanguino pcb. Another interesting item is that there is only 6 cent difference in price. Update: Downloading the Sanguino ZIP file indicated that the ATmega1284P is also included in their design.

Maniacbug site has the most useful data for this project and, in particular, have integrated the ATmega1284P into the Arduino IDE 1.0 environment. So the next step is to determine board size and pin assignments. Since I have already designed a through hole Arduino clone, transfering the power section to the Daiduino will be the first step. That process created a board 3.4" by 2.1".

For pin assignments, there are two designs on the Web to look at, Calunium and Bobuino.. Of the two the Calunium can use a standard shield, but is only USB powered. There is limited information on the Bobuino, but Maniacbug includes it in his zip file.

  1. Same width as the Arduino but longer, 2.1" by 3.5"
  2. Basic set of stacking connectors, UNO
  3. Dual regulators for 3.3V and 5V
  4. Power source: USB or wart
  5. USB interface on a plug in, such as a BUB II
  6. Through hole parts with the exception of the regulators.
  7. LED's, reset switch and ISP at front of the board
  8. Jumpers A4, A5 to I2C for UNO compatibility
  9. Jumper Auto Reset
Note: First version PCB ready for Batchpcb, 06/18/12. Ordered 06/19/12