oSerialPort Object

When a value is written to the Value property the value is sent serially out I/O Line 22 and when a value is received serially from I/O line 23 it is stored in a 4-byte buffer and the Received property is set to 1 (cvTrue). After the Received  property is set to 1 (cvTrue). Reading the Value property will read a byte out of the 4-byte buffer in a first-in-first-out fashion. If only one byte was in the buffer as the time that is was read then the Received property is set to cvFalse.

The value of the Received property can be link to an oDio1 Object that has its Direction property set to cvOutput thereby providing flow control for incoming serial data.  The device sending the serial data will be expected to stop sending the serial data while the output of the oDio1 Object is at +5 Volts.  If the device sending the serial data sends more than 3 bytes after the Received property is set then the 4-byte buffer will be overrun and data will be lost.

The Baud property specifies at which baud rate to send and receive data .  It can specify a baud rate of 1200, 2400, 4800, 9600, 19200, 31500, 38400, or 50000 Baud.

The serial input and output signals are TTL level signals providing 0 and 5 volts. Conversion to RS232 signals can be done with a TTL to RS232 signal converter chip such as the SN75188 or the MAX203 which will provide the voltage conversion to the RS232 levels of +12 and -12 Volts as well as providing the required signal inversion.

CAUTION: do not connect RS232 signals lines directly to the ooPIC's TTL level I/O.  The higher voltage of the RS232 lines will damage the TTL level circuitry.

When created, the oSerialPort Object also creates an instance of the oSerialH object which it uses to do the actual serial transmissions and receptions.  Most properties of the oSerialH instance can be adjusted and will affect the oSerialPort Object's operation. See the oSerialH Help for more detail on how serial data transmissions are made and received.

Each dimensioned instance of the oSerialPort Object internally uses this single serial communications module and thus only one instance may be active at any given time. Setting the Operate property to 1 activates an instance of the oSerialPort Object and will deactivate any other object that also uses the serial communications module which were previously activated.

The following table lists the properties of the oSerialPort Object:

Property	Description
Value	The value of the received data. If written to, transmits data. Object Class:  oFIFO4   Value Range:  0 - 255 Data Type:  Numeric   Default Value:  0 The Value property is a First-In-First-Out (FIFO) Object.  This object holds up to 4 bytes of data from the serial port which returns the the first byte received first and the last byte received last.
Received	A value that indicates if data has been received. Object Class:  oLogic   Value Range:  0 - 1 Data Type:  Numeric   Default Value:  0 Set when 8 bits of data have been successfully received. Cleared when the last byte of the 4-byte buffer is read via the Value property. Received Constant Description 0 cvFalse No new data has been received. 1 cvTrue New data has been received.
IOLineF	A value that specifies which I/O Line to use for Flow Control. Object Class:  oIOLine   Value Range:  0 - 31 Data Type:  Numeric   Default Value:  0 The IOLineF property is available as of Firmware version C.1.0. Some I/O Lines have special purposes.  Be sure to see oIOLine help file for details.
Baud	A value that specifies the baud rate which controls the speed of the serial data stream. Object Class:  oProperty   Value Range:  0 - 15 Data Type:  Numeric   Default Value:  0 When the Baud rate property is set, the Operate is checked.  If the Operate property is 1, then the Baud rate is set into the serial communications module's baud rate register.  If the Operate property is 0, then the serial communications module's baud rate register remains unchanged until the Operate property is set to 1. The following table lists the values of the Baud property: Baud Constant Description 0 cvMidi Serial data communicates at 31,250 Baud. (Midi) 1 cv1200 Serial data communicates at 1200 Baud. 2 cv2400 Serial data communicates at 2400 Baud. 3 cv9600 Serial data communicates at 9600 Baud. 4 cv19200 Serial data communicates at 19,200 Baud. (Available as of firmware version B.1.0) 5 cv4800 Serial data communicates at 4800 Baud. (Available as of firmware version B.1.0) 6 cv50000 Serial data communicates at 50,000 Baud. (Available as of firmware version B.1.0) 7 cv38400 Serial data communicates at 38,400 Baud. (Available as of firmware version B.2.0)
Operate	A value that selects whether or not serial data will be received or sent. Object Class:  oOperate   Value Range:  0 - 1 Data Type:  Numeric   Default Value:  0 Operate Constant Description 0 cvOff The serial port is not operating. 1 cvOn The serial port is operating at the specified baud rate.
Serial	The I/O object used that provides the serial I/O functions. Object Class:  oSerialH   Value Range:  0 - 255 Data Type:  Numeric   Default Value:  0
Address	Returns a pointer to the address of the oCounter Object instance. Object Class:  oAddress   Value Range:  0 - 127 Data Type: Pointer (Read Only)   Default Value:  Address of Object

' This program uses an oSerialPort Object pointed to an ' oDio1 Object for CTS flow control on I/O Line 18. ' First it sends "Hello" out the serial port. ' Second it stores all incoming serial data to ' an EEPROM that is plugged into the E1 Socket. Dim S As New oSerialPort Dim W As New oWire Dim CTS As New oDIO1 Dim E As New oEEProm Sub Main() CTS.IOLine = 18 CTS.Direction = cvOutput E.Node = cvE1 E.Location = 0 S.Baud = cv9600 S.Operate = cvTrue W.Input.Link(S.Received) W.Output.Link(CTS.State) W.Operate = cvTrue S.Value = "Hello" Do If S.Received Then E.Value = S.Value End If Loop End Sub

The property ReceivedOut is no longer supported.  It has been replaced with the IOLineF property in Firmware C1.

Bugs: No known bugs.