Marantz PD5020D manual External Control, Application, Connections, Communication Format, Command

External Control

Application

These specifications cover the communications control of the plasma monitor by external equipment.

Connections

Connections are made as described below.

plasma monitor	External equipment
	e.g., Personal computer

1)Connector on the plasma monitor side: EXTERNAL CONTROL connector.

Type of connector: D-Sub 9-pin male

No. Pin Name

1No Connection

2RXD (Receive data)

3TXD (Transmit data)

4DTR (DTE side ready)

5GND

6DSR (DCE side ready)

7RTS (Ready to send)

8CTS (Clear to send)

9No Connection

1 2 3 4 5

6 7 8 9

Communication Format

8 bit 8 bit 8 bit 8 bit 8 bit 8 bit 8 bit 8 bit

Command 1

Unit ID 1

Unit ID 2

Command 2

Data length

Data

Check sum

Command 1

Command 1, along with command 2, is a number used to distinguish each command.

In the case of ACK, when the lower order 4 bits is FH (as in 3FH and 7FH), this indicates that the commands and data of the supported equipment have been received. When the lower order 4 bits is BH (as in 3BH and 7BH), this indicates that unsupported commands and data have been received.

Unit ID 1 and Unit ID 2

Unit ID 1 and unit ID 2 are numbers used to identify the equipment that is to be connected.

60H is used for the plasma monitor and 80H is used for external control equipment such as a personal computer.

1)Unit ID 1: Indicates the equipment sending the signal

2)Unit ID 2: Indicates the equipment receiving the signal

Command 2

Command 2, along with command 1, is a number used to distinguish each command.

2)Connector on the external equipment side: Serial port (RS-232C) connector.

See the specifications of the equipment that is to be connected for the type of connector and the pin assignment.

3)Wiring

Use a crossed (reverse) cable.

Wire the cable so that each pair of data lines cross between the two devices. These data line pairs are RXD (Receive data) and TXD (Transmit data), DTR (DTE side ready) and DSR (DCE side ready), and RTS (Ready to send) and CTS (Clear to send).

Check Sum (CKS), Error Processing, and ACK

1)The check sum described below and RS-232C odd parity are used together for a check of the received data. The check sum is the lower order 8 bits of one frame of sent or received data comprising the sum total of Command 1, Unit ID 1 and 2, Command 2, Data Length, and Data.

Check Sum Example

DFH	80H	60H	47H	01H	01H	08H
Command 1	Unit ID 1	Unit ID 2	Command	2 Data Length	Data	Check Sum
						▲

Total 208H

Communication Parameters			2) Error Processing
			•	When the communication interval is vacant for more
(1)	Communication system	Asynchronous		than 4 ms, thereafter a received Command 1 will be
(2)	Interface	RS-232C		recognized. If, at this time, meaningful data cannot
(3)	Baud rate	9600 bps		be recognized, that data will not be recognized (as
(4)	Data length	8 bits		valid data).
(5)	Parity	Odd	•	An ACK will not be returned unless the receive data
(6)	Stop bit	1 bit		error, the check sum error, and the receive data are all
(7)	Communication code	Hex	41	taken in.