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Atmel ATMEGA Development Board

A few week ago I bought 5 piece  of ATMEGA88-PU on second-hand market  (www.vatera.hu).The cost was holly low about 0.3$/piece.
I'm going to design and make my own arduino like development board for easy prototyping . I used Eagle Cad for designing the PCB and I used  toner transfer method for etching the PCB . Finally my first DIY PCB and my devboard for atmega88 is ready to go.
This was the first prototype:

Pin header for PORTB,PORTC and PORTD,ISP for Programing,GND and Vcc headers and Reset button
1 weeks later I realised some weaknesses:
  • the power headers was broke
  • I need to plug 2 usb device into my PC.A programer and an USB-Serial converter
  • I can't see any heartbeat (onboard leds) 
I pimped up my board with some goodness:
  • Arduino bootloader for programing over UART ( thx )
  • Extended Power headers 
  • Onboard dual leds and voltage regulator
The other stuff on the left side is USB to Serial converter from SonyEricsson USB Data cable.
The full cost of this development board is about 1.5$:

UPDATE:
Another PCB needed of course,this is ugly and unusable in some situation.I have been using KiCad instead of Eagle Cad.
  • Another problem is the ADC-is not properly beaked out
  • wires usually not connected
  • no option for 5V power because the onboard 3.3V LDO is not changeable

Future plans:
  • 5V-3.3V changeable voltage level
  • 6 pin SPI header OR 10 pin SPI,UART header
  • socket for crystal oscillator
  • ?onboard potentiometer for 1 ADC channel. Sometime be helpful
  • ?arduino compatibility header
  • ?onboard USB -- SERIAL converter
UPDATE:
I get serius about making pcb at home so I order some of this toner tonsfer paper.
It is doing the job, I get much better and errorless results.I completly redisegned my devboard ( I think you know why XD)
Now it has

  • onboard USB-Serial converter (PL2303) with uUSB connector
  • 5V and 3V3 operation
  • laminated front cover as silkscreen
  • Crystal Oscillator header
  • 6pin ISP header
  • Serail port brekout

Redesigned devboard for MEGA88
Furute plans:
  • Selectable power between onboard regulator or powered from ISP
  • Fixing ISP header pinouts (it is not the standard pinouts yet)
Update:

New devboards on the way based on Atmel ATMEGA32 (JTAG Baby!)
The leftmost board maybe the prototype of the new Samsung Galaxy S8 XD.
Rounded edges look's nice.



Of course I fucked up the pin order of SPI header...  




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