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HOW TO RETRIVE DATA
1. Interface
An asynchronous serial format is-employed as the com-
munication interface. The details are as follows.
1-1, Format
1-1-1, Connector Pins
Pins are 9-pin D-SUB. The pin functions are explained be-
low.
PinNo. | Name | Function
Signal Level
1
GND | Signal ground
2
TXD | Transmitted data
RS-232C
3
RXD | Received data
RS-232C
4
DTR | Data terminal ready
RS-232C
5
CTS}
Clear to send
RS-232C
6
RTS | Request to send
RS-232C
7
GND | Frame ground
8
DSR
| Data set ready
RS-232C
9
N.C.
| Not connected
RS-232C
1-1-2. Signal Level
The signal level conforms to RS-232C standards.
1-1-3. Data Format
Start bit: 1 bit Mark state
Data bits: 8 bits
Stop bit: t bit Space state
1-1-4. Transmission Speed
Can select either 2400 bps or 1200 bps by "BAUD RATE:
7" of the FUNCTION switch on the commander inside the
MAIN UNIT DOOR.
1-2, Communications Protocol
Computer
CIVOSICI-N77
(26-pin)
GND 1
gira
1. GND
TXD 2
———_
3RXD
RXD 3
—
21xO
ATS 4
———>
8 OSR
cTS5
—
4DTR
DSRE
rea
6 RTS
GND 7
7 GNO
DTR 20
_——
5CTS
The basic procedure takes the form of first transmitting a
command
from the computer to the CJ-V9S/CJ-V77.
A
response to this command
is then transmitted from the
CJ-V99/CJ-V77 to the computer in the proper form.
The CJ-V99/CJ-V77 is ready to be accessed by the com-
puter if the menu door is open and the player is completely
stopped. However, commands for transmitting data can-
not be unconditionally processed.
First, the password is
checked and the next command is processed in accor-
dance with the result. An error code is returned if the pass-
word is incorrect. Then, an error code is returned to sum-
marize processing for the next command.
To terminate
transmission,
input the password
agai
Data can be released or closed by inputting the password.
2. Command and Exchanges
'The ASCil codes are the characters used for communica-
tion. The command characters stand for the letters of the
alphabet and allow distinction between uppercase and
lowercase letters. Prefixed numeric characters define ar-
guments, and suffixed numeric characters define data.
Commands
must be accompanied
arguments. Data may
be accompanied or not accompanied by commands.
A command and an argument, or a command and data
must not have a space or other additional character codes
inserted between them.
The CR {ODh) code is used as the character terminator.
This code must always be inserted at the end of a string of
command characters, The CJ-V99/CJ-V77 does not inter-
pret any of the codes input before this character termina-
tor, and the codes are not transmitted no matter how
many are input. Additionally, input of the character termi-
nator code only will result in no codes being transmitted,
The command
buffer can
hold
up
to 200 characters,
However, commands must be input one type at a time. If
different types of commands
are entered in succession,
only the first command will be recognized, and the other
commands will be ignored. Additionally, if a command ac-
companies a data code at this point, error processing will
result from the continuation of commands because alpha-
betic characters exist in an area reserved for numeric
characters.
The completion code and the error code are provided as
status codes for commands. The comptetion code is :(3Ah},
This code is transmitted when the last instruction has
been completed. The error code is Exx (xx denotes a two-
digit number}, and the error type is indicated by the numer-
ic value of "xx". CR (ODh} is also used for the character ter-
minator of the status.
2-1. Commands
The commands consist of the following four types.
1. Input command |
2. Request command R
3. Clear command C
4. Set command S
Format:
argument I data CR:
argument RCR
argument CCR
argument S data CR
See note 1.
Note 1:
CR denotes the carriage return code (ODh).
ts
The object of the command is specified by the argument. Argu-
ments include the numbers 1 through 728, However, the upper
limit of arguments for commands is less than 128. There are not
128 commands at the present time. The numbers through 128
are provided for future additions.
Data:
Data consists of values to be input or set in accordance with a
command. Ali data codes are numbers.
45
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