Roboaudiostix I/O pins

Top of RoboAudioStix
This photo shows the top of the RoboAudioStix board. The black circles correspond to ground pins, and the blue squares are around pin 1. For the 2 x N connectors, the even numbered pins are on the egde of the board, and the odd numbered pins are towards the inside of the board



Bottom of RoboAudioStix
This photo shows the bottom of the RoboAudioStix board.



I/O Pins
Looking at the top of the roboaudiostix, and starting in the top left corner, each section of pins will be described.

Pulse Width Modulation (PWM)
The PWM pins have the center row of pins connected to V_MOTOR, which is jumpered to the BOARD connector. This feature was designed to allow R/C servos to be plugged in directly to the robostix. If you plan on using servos on the PWM pins, then you should cut the jumper and provide a separate supply for driving the servos.

MOTOR Power
The two pin MOTOR connector is used to provide power to the center row of the PWM pins (typically used for servos). The pin at the edge of the board is ground and the pin towards the inside of the board is positive (this is backwards from the robostix).

There is a hole labelled V0 right next to the positive MOTOR pin. V0 connects to BOARD. If you want the center row of pins on the PWM connectors to be connected to BOARD, then install a jumper between V0 and the MOTOR positive hole.

BOARD Power
The two pin board connector is used to provide power to the robostix. The pin next to the edge of the board is ground, and the pin towards the inside of the board is positive.

GPIO 5V B
The GPIO_5V_B 2x5 header contains 5v GPIO lines connected to the ATMega128.

ADC ATMega
The 2x5 ADC_ATMEGA header contains 5v ADC pins connected to the ATMega128.

Audio
The 2x3 audio header is connected to the USB1400.

ADC UCB
The 2x5 ADC_USB header contains 3.3v ADC pins connected to the UCB1400.

Gumstix (aka console or FFUART)
The 1x4 GUMSTIX connector brings out a 5v version of the FFUART pins from the hirose connector.

Note that on rev. 816 of the Roboaudiostix, the silk-screen on the solder side labels both pins 2 and 4 as "RXD". Pin 2 is still TxD as in the above table.

GPIO 5V A
The 2x10 GPIO_5V_A pins are 5v GPIO pins connected to the ATMega128.

In System Programming (ISP)
The 2x5 ISP header is used for in system programming. These pins should only be used for in system programming when nothing is plugged into the hirose connector.

GPIO 3.3v
The 2x5 GPIO_3.3V header contains 3.3v GPIO pins connected to the UCB1400.

UARTS
The 2x8 UARTS connector contains a 5v version of the STUART serial port (from the gumstix), two 5v uarts from the ATMega128, and a 5v I2C bus, which connects to both the robostix and the gumstix.

Internal Connections
This section describes the internal connections between the gumstix and the robostix.