Yaesu FT-757GX II, Техническое дополнение

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CAT SYSTEM SER IAL I NTER FACE DATA MA N U A L
The CAT (Computer-Aided Transceiver) System in
the FT-757GX allows use of an external micro­
computer to control the memory and operating
frequency functions of the transceiver. Control
signals are passed to the transceiver on a serial data
line, accessible at the EXT CNTL jack on the rear
of the transceiver. Yaesu offers a number of
different Interface Units for making the neces-
EXT CNTL PINOUT
A/D,
PIO
510
PIN
NAME
1 GND
EXTERNAL INTERFACE
PTO·
SOLA
UFFER
sary data format conversions to connect some of
the common brands of microcomputers. Software
is provided with some of the Yaesu Interface
Units when they are designed for use with one
specific microcomputer. The EXT CNTL jack
also provides access to the receiver AGC line,
for application in user's programs.
FT·757GX
EX CNTL
JACK
BUFFER
AGC LINE
SI
2
3
SI
AGC
Serial Input: accepts standard TTL-level data.
Automatic Gain Control: analog signal output ranging
from +0.4V DC during strong signal reception, to
+2.6V DC when no signal is being received.
DATA TIMING FORMAT
(4800 bits/second)
Start
Byte bit
D0 DI D2 D3 D4 D5 D6
Stop bit
��;
n)
s
--t
r
M
208
µs
5 -byte Command
LSD (D
\]) @ M
SD
@
Format
Shown below are examples of two basic types of
commands. Each is five bytes in length.
Frequency Enter Command
(Example: to set 14.25000
MHz)
00 50 42 01 0A
Frequency
In
!
truction
Parameter (freq. set)
Frequency Step Command
(Example: to step up 500 k
Hz
)
00 00 00 00
07
Parameter
(dummy
(500UP)
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