•Pin 7 SGND (Signal Ground)
•Pin 2 TD (Transmit Data from logic analyzer)
•Pin 3 RD (Receive Data into logic analyzer)
The additional lines you use depends on your controller’s implementation of
the extended hardwire interface.
•Pin 4 RTS (Request To Send) is an output from the logic analyzer which
can be used to control incoming data flow.
•Pin 5 CTS (Clear To Send) is an input to the logic analyzer which
controls data flow from the logic analyzer.
•Pin 6 DSR (Data Set Ready) is an input to the logic analyzer which
controls data flow from the logic analyzer within two bytes.
•Pin 8 DCD (Data Carrier Detect) is an input to the logic analyzer which
controls data flow from the logic analyzer within two bytes.
•Pin 20 DTR (Data Terminal Ready) is an output from the logic analyzer
which is enabled as long as the logic analyzer is turned on.
The TD (Transmit Data) line from the logic analyzer must connect to the RD
(Receive Data) line on the controller. Likewise, the RD line from the logic
analyzer must connect to the TD line on the controller.
The RTS (Request To Send), is an output from the logic analyzer which can
be used to control incoming data flow. A true on the RTS line allows the
controller to send data and a false signals a request for the controller to
disable data transmission.
The CTS (Clear To Send), DSR (Data Set Ready), and DCD (Data Carrier
Detect) lines are inputs to the logic analyzer, which control data flow from
the logic analyzer. Internal pull-up resistors in the logic analyzer assure the
DCD and DSR lines remain high when they are not connected. If DCD or
DSR are connected to the controller, the controller must keep these lines
along with the CTS line high to enable the logic analyzer to send data to the
controller. A low on any one of these lines will disable the logic analyzer data
transmission. Pulling the CTS line low during data transmission will stop
logic analyzer data transmission immediately. Pulling either the DSR or DCD
line low during data transmission will stop logic analyzer data transmission,
but as many as two additional bytes may be transmitted from the logic
analyzer.
Programming Over RS-232C
Extended Interface with Hardware Handshake
3–5