Table of Contents
Combo board
Combo board brings together three different Homelab boards, that makes it ideal usage for robots. Combo board functionality is compatible with Sensor module, Motor module and Communication module.
Combo board is able to drive following motors:
- 4 x DC motors
- 1 x Stepper
- 2 x Servomotor
Connect following sensors:
- 4 x analog
- 4 x digital
- 2 x coder
- 8x digital inputs trough parallel to serial converter
Use the following communication interfaces:
- UART (3,3 or 5 V )
- ZigBee / Bluetooth / RFID / WiFi / GPS wireless communication module
For standard, Combo board uses ZigBee wireless communication module.
Combo board with XBee module
Electrical connections
Combo board is connected with controller using PA-PB-PC-PD-PE-PF ports. DC and stepper motor feeds come from external power cord, servo motors feed comes trough 5V voltage regulator also from external power cord. Motors power circuit is separated from controller's power circuit. If external power feed is correctly connected to the Combo board the green PWR led will lit.
DC motors
DC motors is connected to the DC group of pins. Every pair of pins can control 1 dc motor, thus it's possible to manipulate 4 dc motors. Combo board uses bd6226fp H-bridge to control dc motors. It's possible to manipulate some other device, what can be controlled digitally and it's current is smaller than 1 A and voltage does not exceed 18 V, beside dc motor with DC pins (Piezoelectric generator, relay etc).
DC motor connection scheme
| AVR pin | Signal | AVR pin | Signal |
|---|---|---|---|
| PB4 | Motor 1 A | PD6 | Motor 3 A |
| PB7 | Motor 1 B | PD7 | Motor 3 B |
| PD0 | Motor 2 A | PD4 | Motor 4 A |
| PD1 | Motor 2 B | PD5 | Motor 4 B |
Stepper motor
Stepper connection scheme
Servomotor
Servo is connected to Servo group of pins. Ground wire is connected to the GND pin which is the pin nearest to the board edge. It's possible to use 2 servomotors at once. Signal pins on the Combo board is directly connected to the controller's timer's output pins.
Servomotor connection scheme
| AVR pin | Signal | Socket |
|---|---|---|
| PB5(OC1A) | PWM1 | Top |
| PB6(OC1B) | PWM2 | Bottom |
Sensors
ADC sensor inputs
Combo board has 4 ADC input pins, every ADC input pin forms a group with Vcc (+5 V) and ground which is marked as GND, that makes them ideal to use to connect analog sensors.
Analog sensor inputs scheme
| AVR pin | Signal | Socket |
|---|---|---|
| PF0(ADC0) | ADC0 | Top |
| PF1(ADC1) | ADC1 | Bottom |
| PF2(ADC2) | ADC2 | Top |
| PF3(ADC3) | ADC3 | Bottom |
Digital inputs
Combo board has 4 groups of pins where to connect digital sensors. Every group consist of +5 V also called Vcc, ground also called GND and signal pin.
Digital sensor connecting scheme
| AVR pin | Signal | Socket |
|---|---|---|
| PE2(XCK0/AIN0) | PE2 | Top |
| PE3(OC3A/AIN1) | PE3 | Bottom |
| PE4(OC3B/INT4) | PE4 | Top |
| PE5(OC3C/INT5) | PE5 | Bottom |
Digital serial input
Combo board has with 8 input pins parallel in serial out shift register 74HC/HCT165, what is able to read in 8 digital signals and convert it to 8 bit digital number. Those inputs are suitable for line follower applications.
Shift register connection scheme, odd pins are on top
| AVR pin | Signal |
|---|---|
| PA7(AD7) | Q7 |
| PC7(A15) | CP |
| PA6(AD6) | PL |
| GND | CE |
Coder
Coder connection scheme
| AVR pin | Signal |
|---|---|
| PE6 | Coder 1 |
| PE7 | Coder 2 |
Wireless module
One of these modules can be connected to the Combo board:
- ZigBee module
- Bluetooth
- GPS module
- RFID module
- Wifi module
All of these module communicate over the UART interface with the microcontroller. Also it's possible to connect with a cable external UART device. For external device supply voltage can be chosen 3,3 V or 5 V.
Wireless connection scheme
ZigBee XBee module
| Pin from wireless module | Signal | Socket |
|---|---|---|
| 15(ASSOC/AD5/DIO5) | XADC0 | XBEEADC2 |
| 17(COORD_SEL/AD3/DIO3) | XADC1 | XBEEADC3 |
| 18(AD2/DIO2) | XADC2 | XBEEADC4 |
| 19(AD1/DIO1) | XADC3 | XBEEADC5 |
| 20(AD0/DIO0) | PWR | Connected with robot's power supply |
| 11(RF_TX/AD4/DIO4) | DIO4 | test LED (yellow) |
| 16(RTS/AD6/DIO6) | RST | Reset pin form controller module |
Combo board is connected with 4 wireless module's i/o pins, which can use volt divider, if in use is/are analog input(s) or use as digital i/o. For addition to 4 i/o pins one of wireless module pin is connected with test LED.
