Information from the butterfly and mega169 datasheets...
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butterfly-ports.png

PortB pin connections

Connected to the Port B header, ISP header, Dataflash, and Joystick. Note that for joystick buttons, "The common line of all directions is GND. This means that internal pull-up must be enabled on the ATmega169 to detect the input from the joystick."

|| '''Pin''' || '''Alias''' || '''Connected to...''' || || PB0 || !SS/PCINT8 (SPI Slave Select input or Pin Change Interrupt8) || Dataflash CS pin || || PB1 || SCK/PCINT9 (SPI Bus Serial Clock or Pin Change Interrupt9) || Dataflash SCK pin, ISP Header (pin 3) || || PB2 || MOSI/PCINT10 (SPI Bus Master Output/Slave Input or Pin Change Interrupt10) || Dataflash SI pin, ISP Header (pin 4) || || PB3 || MISO/PCINT11 (SPI Bus Master Input/Slave Output or Pin Change Interrupt11) || Dataflsah SO pin, ISP Header (pin 1) || || PB4 || OC0A/PCINT12 (Output Compare and PWM Output A for Timer/Counter0 or Pin Change Interrupt12) || Joystick center (O) || || PB5 || OC1A/PCINT13 (Output Compare and PWM Output A for Timer/Counter1 or Pin Change Interrupt13) || dunno!! || || PB6 || OC1B/PCINT14 (Output Compare and PWM Output B for Timer/Counter1 or Pin Change Interrupt14) || Joystick up (A) || || PB7 || OC2A/PCINT15 (Output Compare and PWM Output A for Timer/Counter2 or Pin Change Interrupt15) || Joystick down (B) ||

PortD pin connections

Connected to the Port D header and the LCD panel.

|| '''Pin''' || '''Alias''' || '''Connected to...''' || || PD0 || ICP1/SEG22 (Timer/Counter1 Input Capture pin or LCD front plane 22) || LCD15 || || PD1 || INT0/SEG21 (External Interrupt0 Input or LCD front plane 21) || LCD16 || || PD2 || SEG20 (LCD front plane 20) || LCD18 || || PD3 || SEG19 (LCD front plane 19) || LCD13 || || PD4 || SEG18 (LCD front plane 18) || LCD11 || || PD5 || SEG17 (LCD front plane 17) || LCD12 || || PD6 || SEG16 (LCD front plane 16) || LCD14 || || PD7 || SEG15 (LCD front plane 15) || LCD9 ||

PortE pin connections

Connected to USI header, the Joystick, the Dataflash, and UART circuitry.

Note that pins 4-6 are connected to the USI header and nothing else. If you aren't using USI, these pins might be convenient to use for other purposes.

|| '''Pin''' || '''Alias''' || '''Connected to...''' || || PE0 || RXD/PCINT0 (USART Receive Pin or Pin Change Interrupt0) || UART circuit || || PE1 || TXD/PCINT1 (USART Transmit Pin or Pin Change Interrupt1) || UART circuit || || PE2 || XCK/AIN0/ PCINT2 (USART External Clock or Analog Comparator Positive Input or Pin Change Interrupt2) || Joystick left (C) || || PE3 || AIN1/PCINT3 (Analog Comparator Negative Input or Pin Change Interrupt3) || Joystick right (D) || || PE4 || USCK/SCL/PCINT4 (USART External Clock Input/Output or TWI Serial Clock or Pin Change Interrupt4) || USI Header (pin 1) || || PE5 || DI/SDA/PCINT5 (USI Data Input or TWI Serial DAta or Pin Change Interrupt5) || USI Header (pin 2) || || PE6 || DO/PCINT6 (USI Data Output or Pin Change Interrupt6) || USI Header (pin 3) || || PE7 || PCINT7 (Pin Change Interrupt7), CLKO (Divided System Clock) || Dataflash reset pin ||

PortF pin connections

Connected to the temperature circuit, voltage reader circuit, light sensor circuit, and JTAG header.

Note that if you aren't using the JTAG interface, pins 4-7 might be convenient to use for other purposes.

|| '''Pin''' || '''Alias''' || '''Connected to...''' || || PF0 || ADC0 (ADC input channel 0) || Temperature sensor circuit || || PF1 || ADC1 (ADC input channel 1) || Volatage reader circuit || || PF2 || ADC2 (ADC input channel 2) || Light sensor circuit || || PF3 || ADC3 (ADC input channel 3) || VCP - VC-peripheral output, connected to the light sensor and temp sensor || || PF4 || ADC4/TCK (ADC input channel 4 or JTAG Test ClocK) || JTAG header (pin 1) || || PF5 || ADC5/TMS (ADC input channel 5 or JTAG Test mode Select) || JTAG header (pin 5) || || PF6 || ADC6/TDO (ADC input channel 6 or JTAG Test Data Output) || JTAG header (pin 3) || || PF7 || ADC7/TDI (ADC input channel 7 or JTAG Test Data Input) || JTAG header (pin 9) ||