Connections

Your BotBoard Plus has several connectors onboard. This page is intended to help explain what these connectors are for, and how you can interface to them.

As you can see on the left, the BotBoard Plus has 12 connectors onboard. These connectors give you quite a bit of flexibility in connecting your BotBoard Plus to off board devices and other modules. Each connector has its own specific layout, which will be described below.

The connectors on the BotBoard Plus are all considered to be 'Header' style connectors. That means they are all male pins that are spaced on 100mil centers (.100" centers). This spacing is a standard one, and will allow for a wide range of mating connectors.

As a rule of thumb, all connectors have pin 1 as a ground pin. Pin 1 is usually designated as the square pad. As you can see in the picture above, all parts have Pin 1 with a square pad. All connectors also have pin 2 as a +5volt pin. The other pins in the connectors depend on the specific port you are using.

Each 2x5 connector has the following layout when looking from the top. These connectors are designed to use standard IDC socket connectors for use with ribbon cable.

Typical parts you can use are the CW Industries series (Digikey #CSC10G-ND) or an AMP #499997-1 (Digikey #ASC10G-ND). These are a common surplus part as well.

IDC Connectors are typically used with ribbon cable, and almost always are for use with dual row headers. That is because the ribbon cable conductors are spaced 0.050" apart, with the pins at 0.100". IDC stands for Insulation Displacement Connector.

The connection works by forcing the wire between the prongs of a metal fork. The fork cuts through and displaces the insulation, making an electrical connection.

Making a connection can be done using a very expensive IDC crimp tool, or you can use what I came up with. This is a simple pair of slip joint pliers. Notice how the ribbon cable was run through the connector, then the crimped.

The power connector P1 provides Vcc and GND to the board. This is the main supply voltage for the board. The exact value for Vcc can vary from about 4.8 volts to about 6.2 volts without much trouble. It is recommended that you don't exceed 6.4 volts at any time, as damage to the part may result. There is no power switch, so connecting power to this connector will start the board.

PORTA Connector

GND

PORTA:0

PORTA:2

PORTA:4

PORTA:6

+5v

PORTA:1

PORTA:3

PORTA:5

PORTA:7

PORTA is usually used to control the Timer Output Compare and Timer Input Capture functions. They can also be used as input or output pins, depending on the specific pin you are using. See your 68HC11 documentation for specifics.

Note that PORTA:3, PORTA:4, PORTA:5, and PORTA:6 are the same signals as those found on the servo connectors.

PORTB Connector

GND

PORTB:0

PORTB:2

PORTB:4

PORTB:6

+5v

PORTB:1

PORTB:3

PORTB:5

PORTB:7

PORTB is used as an OUTPUT only port.

PORTC Connector

GND

PORTC:0

PORTC:2

PORTC:4

PORTC:6

+5v

PORTC:1

PORTC:3

PORTC:5

PORTC:7

PORTC is available as a bi-directional port. This port is can select which pins are inputs and which are outputs by setting the appropriate bits in the control register DDRC

PORTE Connector

GND

PORTE:7

PORTE:6

PORTE:5

PORTE:4

+5v

PORTE:3

PORTE:2

PORTE:1

PORTE:0

PORTE is an input port, and is typically used for its Analog to Digital capabilities. Note that the pin arrangment is slightly different than the other ports as the pin numbers don't match the port pin numbers directly. This is due to the way that the 68HC11 arranged the pins on the chip. You can also use PORTE as a general purpose digital input port if you wish.

PORTD/SPI Connector

spiport.gif (6634 bytes)

PORTD is split across two different ports.

One primary use of PORTD is as the serial port. Therefore, the RX and TX lines of the serial port are available on the serial connector, shown below.

The other primary use of PORTD is as the SPI port. However, the use of the SPI port is optional, and can be programmed for use as general purpose I/O if needed.

The SPI functions are shown on the left, using the standard labeling provided by Motorola in the 68HC11 specification.

Note that the SPI port is also connected to the serial EEPROM that can be installed on the back of the BotBoard Plus. If you plan to use PORTD for non-SPI purposes, then you should either disable the SPI based serial EEPROM, or not install it.

Check the BotBoard Plus users manual for information about disabiling the serial EEPROM.

The Serial port on the BotBoard Plus provides power and TTL level signals for the SCI port of the 68HC11. Note that you will need a cable that has a converter to make the TTL level conversion to connect it to an RS-232 system.

If you bought the BotBoard Plust Starter kit, then the cable provided in the kit is the correct level converter for use with a standard RS-232 port.

P2 is an optional Servo Power Connector. This allows you to connect an alternate power source for the servo connectors.

You need to cut a jumper on the backside of the board to use this connector. The cut jumper disconnects the Vcc line of P2 from the rest of the BotBoard Plus. GND is still common. You would use this if you need to provide seperate power for running more than 2 servo motors with your BotBoard Plus. See the user manual for more details.

Servo Connectors

servoconnector.gif (6531 bytes)

Each of the 4 servo connectors has the same layout. The Sig line for each connector goes to a specific Timer Output Compare (TOC) pin on PORTA. There are 4 TOC pins on the 68HC811E2. Vcc is connected to P2, and GND is connected to the common ground for the board.

Note that each of the Sig lines of the servo connectors are connected to a pin on the PORTA connector. These signals are shared between the two connectors.