Cat (Computer Aided Transceiver Operation); Cat Data Protocol; Constructing And Sending Cat Commands - Yaesu FT-897D Operating Manual

( C
OMPUTER
The FT-897D's
System allows the transceiver to be
controlled by a personal computer. This allows multiple
control operations to be fully automated as a single mouse
click, or it allows a third-party software package (such as
contest logging software) to communicate with the FT-897D
without (redundant) operator intervention.
The Optional Interface Cable CT-62 is a connection
cable for the FT-897D and your computer. The CT-62 has a
built-in level converter, allowing direct connection from the
rear panel CAT/LINEAR jack to the serial port of your com-
puter, without the need for an external RS-232C level con-
verter box.
Vertex Standard does not produce
software, due to the wide variety of personal computers,
operating systems, and applications in use today.
The information presented in this section will allow the pro-
grammer to understand the command structure and opcodes
used in the FT-897D's
CAT/LINEAR
CT-62 (Option)
FT-897D O M
A
IDED
System operating
System.
RS-232
T
RANSCEIVER

CAT Data Protocol

All commands sent from the computer to the transceiver
consist of five-byte blocks, with up to 200 ms between each
byte. The last byte in each block is the instruction opcode,
while the first four bytes of each block are arguments (either
parameters for that instruction, or dummy values required
to pad the block out to five bytes). Each byte consists of 1
start bit, 8 data bits, no parity bit, and two stop bits.
There are 17 instruction opcodes for the FT-897D, listed in
the chart on next page. Many of these opcodes are On/Off
toggle commands for the same action (e.g. "PTT On" and
"PTT Off") Most of these commands require some param-
eter or parameters to be set. Irrespective of the number of
parameters present, every Command Block sent must con-
sist of five bytes.
Accordingly, any control program must construct the
five-byte block by selecting the appropriate instruction
opcode, organizing the parameters as needed, and provid-
ing unused "dummy" argument bytes to pad the block to its
required five-byte length (the dummy bytes can contain any
value). The resulting five bytes are then sent, opcode last,
from the computer to the FT-897D CPU via the computer's
serial port and the transceiver's
All CAT data values are hexadecimal

Constructing and Sending CAT Commands

Example #1: Set the VFO frequency to 439.70 MHz
Ì Per the
command table, the opcode for "Set Fre-
quency" is 01. Placing the opcode into the 5th data bit
position, we then enter the frequency into the first four
data bit positions:
DATA 1 DATA 2 DATA 3 DATA 4 DATA 5
43 97
Parameter
Send these five bytes to the transceiver, in the order
shown above.
Example #2: Turn the Split Mode "On"
Ì Per the
command table, the opcode for "Split On/
off" is 02. Placing the opcode into the 5th data bit posi-
tion, we then enter dummy values into all other param-
eter locations:
DATA 1 DATA 2 DATA 3 DATA 4 DATA 5
00 00
Parameter
) O
PERATION
/LINEAR jack.
00 00 01
Command
00 00 02
Command
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