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This chapter discusses the options available for customizing a RabbitFLEX BL300F. The options fall into one of three main categories: global, pin group or connector.
Global Options
Global options, as the name implies, have a more global effect on the board design than the options in the other two categories. Global options are things like the core module and serial communication channels.
Pin Group Options
Pin group options are circuits that populate more than one pin on a connector. Things like an LCD or keypad are in this category. Multiple pins are configured when an LCD or keypad is chosen.
Connector Options
Connector options affect one pin on a connector, like digital or analog I/O.
4.1 Overview of Options
This section gives a visual overview of all available options and the connector/pins used.
4.2 Overview of Connector and Cell Association
The table in this section summarizes the user-configurable connectors, their corresponding unconfigured cells and the available circuitry that can be used to configure the cells. (See Section 3.2 for more information about cells.)
2-transistor 2-transistor 2-transistor 1-transistor 1-transistor
4.2.1 Connector Pinout Diagram
This section identifies the location of the connectors and their customizable options.
For obvious reasons, a board-specific pinout diagram is impossible to include in a generally applicable user's manual such as this one. The following diagrams give the pinouts of the user-configurable connectors and the options available for each of the pins. To review the option/pin combinations that exist on your particular board, look in the generated library FAxxxxxxx.lib or the board summary file FAxxxxxxx.txt. These files, which are downloadable from the RabbitFLEX Configurator, tell you which option is connected to each of the configurable pins.
4.2.1.1 Connector 1
Connectors J1 through J5 all have digital I/O, power routing, ground and +K (external power) options. But the range of choices is greater in the digital I/O options for J1 through J3 because the pins are connected to two-transistor cells as opposed to the one-transistor cells of J4 and J5.
Connectors J3 and J4 add the ability to be configured as analog inputs.
If the LCD option is selected, it will populate the 8 available pins of J1.
4.2.1.2 Connector 2
The two DAC channels and the PWM outputs are available on J2. The 0-10 V option requires an external +12 V power supply connected to +K on J2.
4.2.1.3 Connector 3 and 4
The pinout diagram for J4 looks exactly like the one for J3. The difference is that J4 is made up of one-transistor cells and J3 is made up of two-transistor cells. This difference means that, for example, the pins on J4 can be configured for the 100 mA sinking driver or the 100 ohm line driver, but not the 1 A sinking driver or either of the sourcing drivers available on J1, J2, or J3. Also the 3.45 V power supply is not available on J4.
4.2.1.4 Connector 5
If the keypad option is selected, it will populate pins on J5. The number of pins depends on the number of rows and columns chosen. For a 2x3 keypad, six pins are used. For a 4x4 keypad, all eight configurable pins are used.
4.2.1.5 Connector 6
J6 differs from J1-J5, in that its pins can only be customized from the global options page of the RabbitFLEX Configurator. This is because J6 is used for serial communications and the speaker.
4.2.2 Connector Mating Information
The connectors J1 through J6 on the RabbitFLEX BL300F are Molex Micro-Fit 3.0 connectors, Molex part # 43045-1018. There are a number of companies that offer custom harness assemblies that could be mated with these connectors. Molex has a list of recommended cable assembly manufacturers on their website:
www.molex.com/product/harness/stars.htmlRabbit recommends both Blaylock's, Inc. and Mann Organization for custom cable assembly.
www.blaylocksinc.com/www.mannorganization.com/index.html4.3 RabbitFLEX BL300F Option Specifications
This section lists all of the RabbitFLEX BL300F options, along with basic information and specifications.
4.3.1 Core Module
There are currently two core modules available for the RabbitFLEX BL300F: the PowerCore 3800 and PowerCore 3810. The table in this section compares the features that differ between these modules. See the PowerCore FLEX User's Manual for more information about these core modules.
Microprocessor Ethernet Onboard Power Supply Memory As you can see from the information in Table 4-2, the PowerCore 3800 is faster, can communicate on a network, supplies more power and has more memory than the PowerCore 3810. The serial flash on the PowerCore 3800 allows the use of the Dynamic C FAT module, adding a popular standard for file storage to your application. However, if your application requires a low-power solution and only requires serial communication, the PowerCore 3810 would be an appropriate choice.
4.3.2 RS-232
You can select one of the following RS-232 channel configurations:
Serial port F is used for the first 3-wire channel. If you select two 3-wire channels, the second one will use serial port D or E. A 5-wire channel will use serial port F for transmit/receive and serial port D or E for the handshaking lines. Note that whether to use serial port D or E is a decision made when you are designing/ordering your board. Once the board is built you cannot change which of these two serial ports to use.
The API function serMode() allows you to enable or disable hardware flow control.
The serial channel lines come out on J6 (see Figure 4-2). All signals are true RS-232 signals; the board provides the voltage output, slew rate, and input voltage immunity required to meet the RS-232 serial communication protocol. Basically, the signals from the Rabbit 3000 are converted to RS-232 signal levels. The polarity is reversed in an RS-232 circuit so that a +3.3 V input becomes approximately -7 V and 0 V is output as +7 V. The RS-232 transceiver also provides the proper line loading for reliable communication.
The following table lists the different capabilities of the serial ports D and E. More information on these serial ports can be found in the Rabbit 3000 Microprocessor User's Manual.
Asynchronous mode up to the baud rate of the system clock divided by 8 Asynchronous mode up to the baud rate of the system clock divided by 8 Clocked serial mode HDLC SPI device interfacing SDLC An asynchronous port can handle 7 or 8 data bits. A 9th bit address scheme, where an additional bit is sent to mark the first byte of a message, is also supported.
The RS-232 protocol is implemented by the library
RS232.lib, which can be found in the folder named "Lib" where you installed Dynamic C.
4.3.3 RS-485
You can select an RS-485 communications channel with or without termination or jumpered termination for the most flexibility. The header J8, between J6 and the RS-485/RabbitNet port, is the header for RS-485 jumpered termination. J8 pin numbers are marked in Figure 4-8.
See Table 4-4 to determine jumper setting for enabling/disabling termination.
For more information on termination see Section 5.2.
The RS-485 lines come out on connector J6 (see Figure 4-2). Signal A is pin 8 (485+) and signal B is pin 7 (485-). The RS-485 protocol is a packet driver implemented by the library
packet.lib, which can be found in the folder named "lib" where you installed Dynamic C.
4.3.4 RabbitNet
RabbitNet is a high-speed synchronous protocol used to connect peripheral cards to a master and to allow them to communicate with each other. The available peripheral cards are:
For complete information on RabbitNet see the RabbitNet Peripheral Cards User's Manual and then any manuals specific to the peripheral card you are interested in.
4.3.5 LCD
The RabbitFLEX™ SBC Configurator will automatically assign pins from connectors J1 and J2 to interface with the LCD. Pins from J2 are used only if you choose the backlight option (pin 1) and/or the contrast control option (pin 5).
The LCD must have a 4-bit data interface. Note that the RabbitFLEX BL300F LCD driver is intended to support modules based on the Hitachi HD44780 chipset, but we cannot guarantee compatibility will all LCD modules based on this chipset. To ensure compatibility, use the LCD module provided for the RabbitFLEX BL300F in the RabbitFLEX Keypad/Display Kit. For more information on the 4 x 20 character display in the kit, see Appendix D.
4.3.6 Keypad
The RabbitFLEX BL300F is compatible with XY matrix keypads, also known a crosspoint keypads. The keypad options are m x n, where m + n <= 8. The specific options available are:
4.3.6.1 Keypad Inputs
The RabbitFLEX Configurator will automatically assign pins from connector J5 as the keypad inputs and outputs. Keypad inputs and outputs are digital I/O circuits. Keypad inputs are read by the API function
flexKeyProcess(). This function must be called frequently in a software application in order to poll the keypad for key presses. See sample programSamples/RabbitFLEX_BL300F/keypad.cfor an example of how to use the keypad API functions. (The "RabbitFLEX_BL300F" folder was formerly named "RabbitFLEX_SBC40.")
4.3.6.2 Keypad Outputs
The RabbitFLEX Configurator will automatically assign pins from connector J5 as the keypad inputs and outputs. Keypad inputs and outputs are digital I/O circuits. See sample program
Samples/RabbitFLEX_BL300F/keypad.cfor an example of how to use the keypad API functions. (The "RabbitFLEX_BL300F" folder was formerly named "RabbitFLEX_SBC40.")
Power On/Reset State: Off, High impedance
4.3.7 External Interrupt
The external interrupt can be configured to use J1, pin 7 on the RabbitFLEX BL300F. The external interrupt is enabled using the Rabbit's parallel port E, pin 0 (PE0), which is associated with interrupt vector 0, located at EIR:0x000. The following steps must be taken to prepare the external interrupt for use:
Write the interrupt vector to the external interrupt table. The interrupt vector is typically a call to an interrupt service routine (ISR). If it can fit into the 16-byte table entry, it is possible to place the ISR directly into the external interrupt table.
Write to I/O register I0CR to select what edges will be detected and the interrupt priority.
See the Rabbit 3000 Microprocessor User's Manual for more information on interrupts.
4.3.8 External Reset
The external reset can be configured to use J1, pin 8 on the RabbitFLEX BL300F. This master reset input will initialize everything in the Rabbit 3000 except for the real-time clock registers. For more information regarding system reset, see the Rabbit 3000 Microprocessor User's Manual.
When a battery is installed, battery backup of the real-time clock and the RAM selected by /CS1 occurs during reset and powerdown. For more information regarding battery-backed circuits, see the PowerCore FLEX User's Manual.
4.3.9 PWM Outputs
PWM stands for pulse width modulation, which allows the creation of a digital pulse train with a variable on/off duty cycle. This can be filtered to create an analog voltage, or used directly to control many devices, such as lamps or LEDs. Creating an analog voltage then feeding it to an analog driver or amplifier creates a DAC system.
Four PWM outputs are available on a RabbitFLEX BL300F. A Rabbit PWM output has 10-bit resolution and consists of a train of pulses periodic on a 1024-count frame with a duty cycle that varies from 1/1024 to 1024/1024
Each PWM output can be further configured as:
The direct output has the advantage of being a push/pull driver. It has the same current capacity as a general output on the Rabbit: 6.8 mA, sinking or sourcing. A direct PWM output could be used as a control for a high impedence device.
For applications that need more current than is supplied with a direct PWM output, select one of the sinking drivers or the sourcing driver option. The driver options add current to the PWM output, giving it the ability to drive an low impedence load such as a motor or a solenoid.
4.3.10 Digital Inputs
Digital input circuits are available on connectors J1 through J5, pins 1 through 8. For a dedicated digital input, you may select from the following threshold voltages or special purpose inputs:
4.3.10.1 Digital Input 1.4 V Threshold
This section presents the circuit schematic and the characteristics for the 1.4 V threshold digital input.
4.3.10.2 Digital Input 2.8 V Threshold
This section presents the circuit schematic and the characteristics for the 2.8 V threshold digital input.
4.3.10.3 Digital Input 4.4 V Threshold
This section presents the circuit schematic and the characteristics for the 4.4 V threshold digital input.
4.3.10.4 Contact Input
This section presents the circuit schematic and the characteristics for the contact input.
A contact input is designed to be connected to a switch. It has a longer time constant than the other digital inputs to quiet the noise generated by a switch closure. And it already has the pullup allowing simple wiring of the switch between the input and ground. Basically, it is a hardware switch debouncer, though it may be still be neccesary to use software to fully debounce the switch.
4.3.10.5 Bidirectional Logic
This section presents the circuit schematic and the characteristics for the bidirectional logic. A birdirectional logic circuit is useful when talking to an offboard device that communicates using the same line for transmit and receive, such as an I2C device.
4.3.11 Digital Outputs
There are several digital output options on a RabbitFLEX BL300F.They are listed in Table 4-13. Note that not all options are available on all five connectors.
Sinking Driver, 1 A Sinking Driver, 100 mA Sourcing Driver, +K V, 400 mA Sourcing Driver, 5 V, 50 mA (short circuit current limited) Line Driver, 100 Ohm, 5 V
4.3.11.1 Sinking Driver 1 A
This section presents the circuit schematic and the characteristics for the 1 A sinking driver. See Section 5.4.3 for more information on protection diodes.
Power On/Reset State: Off, high impendance
4.3.11.2 Sinking Driver 100 mA
This section presents the circuit schematic and the characteristics for the 100 mA sinking driver. The 100 mA sinking driver does not have the protection diodes that are in the 1 A circuit.
Power On/Reset State: Off, high impendance
4.3.11.3 Sourcing Driver 400 mA
This section presents the circuit schematic and the characteristics for the 400 mA sourcing driver. Note that it has diode protection. This driver sources from the user-supplied +K pin and can handle up to 24 V.
Power On/Reset State: Off, high impendance
4.3.11.4 Sourcing Driver 50 mA
This section presents the circuit schematic and the characteristics for the 50 mA sourcing driver. Note that it has diode protection. This sourcing driver is short circuit current limited to about 65 mA, making it ideal for vending machine applications requiring a short circuit proof driver.
4.3.11.5 Line Driver, 100 W, 5 V
This section presents the circuit schematic and the characteristics for the line driver. Line drivers are available on J1 through J5, pins 1 through 8.
Power On/Reset State: Off, 0 V
4.3.12 Digital-to-Analog Converters
The RabbitFLEX BL300F can have up to two DAC channels. The analog output from channel #0 comes out on J2, pin 7or can be used to drive the optional speaker output (See Section 4.3.12.3). Analog output channel #1 comes out on J2, pin 8. There are two voltage output range options:
There are two things to notice in the circuit schematics for the DAC channels (Figure 4-21 and Figure 4-22). First, the 0-10 V DAC channel uses the op amp to increase the PWM voltage to the desired range. Second, the +K voltage is user-supplied and must be at least +12 V, and no more than 30 V when either DAC channel is set to the 0-10 voltage range.
4.3.12.1 DAC 0-3 V
This section presents the circuit schematic and the characteristics for the 0-3 V DAC.
4.3.12.2 DAC 0-10 V
This section presents the circuit schematic and the characteristics for the 0-10 V DAC.
4.3.12.3 Speaker
DAC channel #0 can be configured as an input to a speaker. A pulse width modulated (PWM) signal goes through a low-pass filter, changing the high speed digital signal from the Rabbit processor into a smoothly varying analog signal. This signal is not strong enough to drive the speaker, so it goes through a low voltage audio power amplifier before connecting to the speaker line. Figure 4-23 is a circuit schematic of the filter/amplifier. The output to the speaker is on J6.
NOTE The operating temperature range for the speaker differs from the operating temperature range (-40°C to +70°C) of the rest of the RabbitFLEX BL300F components. A sample WAV files is provided in
/Samples/RabbitFlex_BL300F/audio/or in/Samples/RabbitFlex_SBC40/audio/depending on your version of Dynamic C.
4.3.13 Analog-to-Digital Converters
The RabbitFLEX BL300F has a ramp-compare ADC. Up to 16 channels are available. The analog inputs can be on any combination of pins 1 through 8 on both J3 and J4. The design of the ADCs allow you to choose a current or voltage input on these pins. The measurement range options are:
The ADCs work with single-ended unipolar voltage inputs and industry standard 4-20 mA current loops.
The digital result has an 8-bit resolution and the sampling frequency is determined by the following equation.
The ADC channels are sampled round-robin, so the sampling frequency depends on the number of analog-to-digital channels that exist on the RabbitFLEX BL300F. If there is only one ADC, the sampling frequency is about 425 samples per second. If the maximum of 16 ADCs exist, the sampling frequency is about 25 samples per second.The ADCs are not meant for applications that require very fast data acquisition rates. They are suitable for measuring analog voltages that change slowly.
4.3.13.1 Analog Input 0-3 V
This section presents the circuit schematic and the characteristics for the 0-3 V analog input.
4.3.13.2 Analog Input 0-10 V
This section presents the circuit schematic and the characteristics for the 0-10 V analog input.
4.3.13.3 Analog Input 4-20 mA
This section presents the circuit schematic and the characteristics for the 4-20 mA analog input.
This analog input provides a simple interface for industry standard 4-20 mA devices. It is a passive input and the device must either supply the loop current or be wired in series with a supply to operate correctly. The loop is formed by using the input pin as the SIG+ line and the ground pin as the SIG- or signal return.
A design consideration for choosing the appropriate ADC circuit for your application is the fact that current is preferred over voltage in noisy industrial/control environments where the transmission of low-amplitude, low-frequency signals must travel significant distances. This is because the current stays constant over the length of the cable.
4.3.14 Power Routing
You can bring power supply pins out on any of the pin-configurable connectors (J1-J5). All five connectors accommodate 5 V pins, but only J1-J3 have 3.45 V. Keep in mind that no matter how many power supply pins are configured, there is a limit to their simultaneous use. The power budget for your application must stay within the parameters of the total power for the system.
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