Windows Protocol; Description; Communication Format; Communication Protocol - Varian Turbo-V 81-AG Bedienungshandbuch

WINDOWS PROTOCOL

DESCRIPTION

Communication Format

•
8 data bit
•
no parity
•
1 stop bit
•
baud rate: 600/1200/2400/4800/9600 programmable

Communication Protocol

The communication protocol is of the MASTER/SLAVE type
where:
•
Host = MASTER
•
Controller = SLAVE
The communication is performed in the following way:
1. the host (MASTER) sends a MESSAGE + CRC to the
controller (SLAVE);
2. the controller replies with an ANSWER + CRC to the
host.
The MESSAGE is a string with the following format:
<STX>+<ADDR>+<WIN>+<COM>+<DATA>+<ETX>+<CRC>
were:
NOTE
When data is indicated between double quotes ("..."), this
means that the data indicated is the corresponding ASCII
character.
- <STX> (Start of transmission) = 0x02
- <ADDR> (Unit address) = 0x80 (for RS 232)
<ADDR> (Unit address) = 0x80 + device number (0 to 31)
(for RS 485)
The controller can answer with the following types of replies:
RESPONSE TYPE RESPONSE LENGTH
Logic
Numeric
Alphanumeric
ACK
NACK
Unknown Window
Data Type Error
Out of Range
Win Disable
RESPONSE VALUE
1 byte
6 bytes
10 bytes
1 byte
1 byte
1 byte
1 byte
1 byte
1 byte
- <WIN> (Window) = a string of 3 numeric character indicating
the window number (from "000" to "999"); for the meaning of
each window see the relevant paragraph.
- <COM> (Command) = 0x30 to read the window, 0x31 to
write into the window.
- <DATA> = an alphanumeric ASCII string with the data to be
written into the window. In the case of a read command, this
field is not present. Field length varies according to the data
type as per the following table:
DATA TYPE
Logic (L)
Numeric (N)
Alphanumeric
(A)
- <ETX> (End of transmission) = 0x03
- <CRC> = XOR of all characters subsequent to <STX> and
including the <ETX> terminator. The value is hexadecimal
coded and indicated by two ASCII character.
The addressed SLAVE will respond with an ANSWER whose
structure depends on the MESSAGE type.
When the MESSAGE is a read command, the SLAVE will
respond transmitting a string with the same structure
Using the RS 485 interface, message structure is identical to
that used for the RS 232 interface, the only difference being
the value assigned
- After a read instruction of a logic window.
- After a read instruction of a numeric window.
- After a read instruction of an alphanumeric window
(0x6) Execution of the command has been completed
successfully.
(0x15) Execution of the command has failed.
(0x32) The window specified in the command is not a valid
window.
(0x33) The data type specified in the command (Logic,
Numeric or Alphanumeric) does not match the win-
dow specified.
(0x34) The value expressed during a write command is
outside the range of value of the window specified.
(0x35) The window specified is Read Only or temporarily
disabled (for example, Soft Start cannot be written
when the Pump is running).6
47/50
TECHNICAL INFORMATION
FIELD LENGTH VALID
CHARACTERS
1 "0" = OFF
"1" = ON
6 "-", ".", "0"..."9" right
justified with "0"
10 From blank to "_"
(ASCII)
NOTE
to the ADDRESS
DESCRIPTION
87-901-004-01 (B)
ADDR>.
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