~&T
System Programming
£AT
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 instruc-
tion, 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.
¢:l
CAT
DATA
BYTE FORMAT
¢:l
CAT
5-BYTE COMMAND STRUCTURE
There are
13
instruction opcodes for the FT-lOO, listed
in
the chart on next page. Many
of
these opcodes are OnJOfftoggle commands for the same action (e.g. "PTT On" and "PTT
Off').
Most
of
these commands require some parameter or parameters to be
set.
Irrespective
of
the number
of
parameters present, every Command Block sent must consist
of
five bytes.
Accordingly, any
~'&T
control program must construct the five-byte block
by
selecting
the appropriate instruction opcode, organizing the parameters as needed, and providing
unused
"dummy" argument bvtes 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-lOO
CPU via the computer's serial port and the transceiver's
ACC
Cable Pigtail.
All
~'&T
data values are hexadecimal.
Note that, unlike most other Yaesu transceivers, the FT-847 serial data cable
is
a "null
modem" ("crossed")
type, not a "straight" serial data cable.
CONSTRUCTING AND
SENDING
CAT
COMMANDS
Example #1: Set the VFO frequency to 439.70 MHz
D
Per the
~'&T
command table, the opcode for "Set Frequency"
is
OA
(set
by
the
"PI"
command byte). 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
¢:J
'-'
_0_0
__
0_0
__
9_7
__
43---,
~
Parameter Opcode
Send these five bytes to the transceiver,
in
the order shown above.
Example #2: Turn the Split Mode
"ON"
D Per the
~'&T
command table, the opcode for "Split
On/off'
is
01
(hex). Placing the
opcode into the 5th data bit position,
we
then enter dummy values into
all
other param-
eter locations:
DATA
1
DATA
2
DATA
3
DATA
4
DATA
5
¢:J
,00
00 00
,~~
Dummy Data
Parameter
Opcode
FT-IOO
MICRO
MOBILE
OPERATING
MANUAL
97
To Next Page
Loading...
Need help?
General
Weight and Dimensions
