Interface Capabilities
The baud rate, stopbits, parity, protocol, and databits must be configured
exactly the same for both the controller and the logic analyzer to properly
communicate over the RS-232C bus. The RS-232C interface capabilities of
the 1660-series logic analyzers are listed below:
•Baud Rate: 110, 300, 600, 1200, 2400, 4800, 9600, or 19.2k
•Stop Bits: 1, 1.5, or 2
•Parity: None, Odd, or Even
•Protocol: None or XON/XOFF
•Data Bits: 8
Protocol
NONE With a three-wire interface, selecting NONE for the protocol
does not allow the sending or receiving device to control dataflow. No
control over the data flow increases the possibility of missing data or
transferring incomplete data.
With an extended hardwire interface, selecting NONE allows a hardware
handshake to occur. With hardware handshake, the hardware signals control
dataflow.
XON/XOFF XON/XOFF stands for Transmit On/Transmit Off. With this
mode, the receiver (controller or logic analyzer) controls dataflow, and,
can request that the sender (logic analyzer or controller) stop dataflow.
By sending XOFF (ASCII 19) over its transmit data line, the receiver
requests that the sender disables data transmission. A subsequent XON
(ASCII 17) allows the sending device to resume data transmission.
Data Bits
Data bits are the number of bits sent and received per character that
represent the binary code of that character. Characters consist of either 7 or
8 bits, depending on the application. The 1660-series logic analyzer supports
8 bit only.
8 Bit Mode Information is usually stored in bytes (8 bits at a time).
With 8-bit mode, you can send and receive data just as it is stored,
without the need to convert the data.
Programming Over RS-232C
Interface Capabilities
3–9