LCD writes, IC2 Pin 25 is driven high, which forces a high (idle) signal to the remote serial device,
thereby preventing any spurious character transmission.
Configuration:
The serial data format is 8-bit, 1 start bit, 1 stop bit, at 38400 baud (bps). No parity is used. This is
the most common serial data configuration normally used in most applications by default.
No flow control is used (no RTS, CTS signals). A CTS signal could be created by a simple
transistor circuit to invert the IC2 PIN 25 signal, which is High during LCD write. This is the
opposite polarity to that required by the CTS signal, which is set low to indicate to the remote
computer that the transceiver is not ready to receive data.
Note that without flow control, there will inevitably be some occasions when the remote computer
queries the QCX+ for information, but the incoming characters arrive during LCD update and are
therefore missed.
CAT command format:
All CAT commands consist of a 2-character command code, optionally followed by a parameter
and a semicolon as the terminator. Commands to SET a parameter in the QCX+ are the 2-
character command code, followed by the parameter value, followed by a semicolon terminator.
Commands to GET a parameter back from the QCX+, are the same but without the parameter
value. For example:
FA00007030000;
Sets the QCX+ VFO A to 7.030MHz
FA;
Asks the QCX+ what the frequency of VFO A is. The QCX+ will
respond with “FA00007030000;” to indicate VFO A is set to 7.030MHz.
All the commands are like this. Two character command code followed by ; to read a value. To set
a value, just insert the parameter value between the two-character command code and the
semicolon terminator. If an invalid command is issued, then a value “?;” is returned. Replies from
the QCX+ do not have carriage return or linefeed characters, only the CAT standard ‘;’ character
(semicolon) as the terminator.
Note that a limited subset of the TS-480 command set is used, due to the limited program space
available in the QCX+ and because many TS-480 transceiver commands are not applicable to the
QCX+. Some of the commands are read-only and cannot be used to write parameters to the
QCX+; an attempt to write (SET) a parameter which in the QCX+ implementation is read-only, will
be ignored; the QCX+ will answer with the parameter reply, just the same as if a read (GET)
command had been issued. The commands implemented should be sufficient for operation with
popular logging programs. Note also that in the interests of compact code, minimal error checking
is undertaken. Setting the VFO frequency to something invalid or out of band is not prevented, for
example.
The following lists the commands and responses in alphabetical order:
AG: Get AF Gain
Get: Always returns 0000 – the audio gain on the QCX+ is an analogue control and the processor
does not have a way of reading it; this CAT command is supported because certain software
requires it to return a value; the actual value 0 returned has no meaning.
AX: Get/Set auxiliary I/O pins.
Set: The two least significant bits of the value are written to the LCD_D6 and LCD_D7 signals. For
QCX operating manual, firmware 1.07, manual edit 0.03
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