
Chapter
9
67
ML-9011A
9.6 Communication Period
The following example describes how to calculate the communication period for VDW (variable data),
relative to the baud rate.
9.6 Communication Period
Example
When setting variable data #7 as follows: 123 in the 2nd standard font, Figure = 1, ITF = 0123
(1) Period when sending from a computer
Data to send: STX VDW7,1,123,2,1,7,0123 ETX Checksum
•
STX
•
VDW7, 1, 123, 2, 1, 7, 0123
•
ETX
•
Checksum
1 character
21 characters
1 character
2 characters
Total: 25 characters
To send one character of each:
•
Start bit
•
Data
•
Parity
•
Stop bit
1 bit
8 bits
1 bit (0 bits)
*
1 bit (2 bits)
*
Total: 11 bits
(Requires 10-12 bits)*
* May be changed to the number of bits in parentheses ( ). 11 bits is the default setting.
That is, 11 bits x 25 characters = 275 bits
If the baud rate is 9600,
275
÷9600 =
28.646 ms
Thus, the time required for transmission is 29 ms.
However, the interval between sending each character will vary with computer
performance and the software configuration.
(2) Response period
The response period varies depending on the type of command, but generally
takes approx. 30-50 ms.
(3) Receiving period when sending from the marker
Example:For one character, assuming that the data to receive is an ACK (with default
settings)
11 bits x 1 character = 11 bits.
*
If the baud rate is 9600,
11
÷
9600 = 1.146 ms
* ETX can be added through the settings.
Thus, it will take approx. 62-82 ms per communication session.
Computer
Controller
Time
Sending Period
Response Period
Receiving Period
Controller
Computer
Transmission
Reception