Component: IO Expander (PCF8574) (Comms: System)
| Author | Matrix TSL |
| Version | 1.0 (Release) |
| Category | Comms: System |
Contents
IO Expander (PCF8574) component
Provides 8 digital input/output pins arranged into an 8-bit port using a I2C bus connection. Up to eight expanders can be connected to the same I2C peripheral by means of three address pins. Supports the PCF8574 and PCF8574A devices allowing up to 16 expanders to be connected to the same I2C bus ( 8 x PCF8574 + 8 x PCF8574A ).
Examples
No additional examples
Downloadable macro reference
ReadPort
Reads a value to one of the ports with a mask.
Configures the masked bits to be inputs before reading the input value.
Parameters
- This macro has no parameters
Return value
WritePort
Writes a value to one of the ports with a mask.
Configures the masked bits to be outputs before writing the output value.
Parameters
- BYTE Value
- Value to write. Range 0-255
Return value
- This call does not return a value
Initialise
No additional information
Parameters
- This macro has no parameters
Return value
- This call does not return a value
Simulation macro reference
This component does not contain any simulation macros
Property reference
Device Type
This property is of type Fixed list of ints and can be referenced with the variable name DeviceType.
No additional information
External Address
This property is of type Fixed list of ints and can be referenced with the variable name ExtAddress.
Selects the value of the three address pins for the MCP23S17.
Channel
This property is of type Fixed list of ints and can be referenced with the variable name cal_i2c1::CHANNEL.
Channel selection
Stop Delay
This property is of type True or false and can be referenced with the variable name cal_i2c1::StopDel.
On older microcontroller devices there is a potential for the I2C hardware channel to lock up if there is not
a 10ms delay between an I2C stop event and the next I2C start event.
Most modern microcontrollers will not have a problem so this property can be disabled to speed up the
I2C communications.
Baud Select
This property is of type Fixed list of ints and can be referenced with the variable name cal_i2c1::BAUD_LIST.
Baud rate option selector
Baud Rate
This property is of type Signed integer and can be referenced with the variable name cal_i2c1::BAUD.
Baud rate to be used
SDA
This property is of type Single digital pin and can be referenced with the variable name cal_i2c1::SDA.
Pin used for SDA (data signal)
SCL
This property is of type Single digital pin and can be referenced with the variable name cal_i2c1::SCL.
Pin used for SCL (clock signal)
Label
This property is of type Line of text and can be referenced with the variable name label.
No additional information
Scope Traces
This property is of type True or false and can be referenced with the variable name cal_i2c1::ScopeTraces.
Selects if the scope traces are automatically generated or not
Console Data
This property is of type True or false and can be referenced with the variable name cal_i2c1::ConsoleData.
Selects if the console data is automatically generated or not
Injector
This property is of type Fixed list of ints and can be referenced with the variable name cal_i2c1::Injector.
No additional information
