12.4.13.1 Example Command Block for the Read String
Function
VALUE
(decimal)
VALUE
(hexadecimal)
MEANING
address 0005 0005
Data block length
address +1 0000 0000 NOWAIT mode
address +2 0008 0008
Status word memory type (%R)
address +3 0000 0000
Status word address minus 1 (%R0001)
address +4 0000 0000 Not used
address +5 0000 0000 Not used
address +6 4403 1133
Read string command
address +7 0030 001E
Read time-out (30 seconds)
address +8 0013 000D
Terminating character (carriage return): must be
between 0 and 255 (0xFF), inclusive
address +9 0008 0008
Input data memory type (%R)
address +10 0100 0064
Input data memory address (%R0100)
12.4.13.2 Return Data Format for the Read String Function
The return data consists of the number of characters actually read, the number of
characters still available in the input buffer after the read is complete (if any), and the
actual input characters:
Address
Number of characters actually read
Address + 1
Number of characters still available in the input
buffer, if any
Address + 2
first two characters (first character is in the low byte)
Address + 3
third and fourth characters (third character is in the
low byte)
Address + n
subsequent characters
12.4.13.3 Operating Note
If the input data memory type parameter is specified to be a word memory type, and if an
odd number of bytes are actually received, then the high byte of the last word to be
written with the received data is set to zero
As data is received from the serial port it is placed in the internal input buffer. If the
buffer becomes full, then any additional data received from the serial port is discarded
and the Overflow Error bit in the Port Status word (See Read Port Status Function) is set.
248 GFK-1503E VersaMax PLC User Manual
For public disclosure
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