Digital Input/Output Bytes And System Variables - Siemens SINUMERIK 840DiE sl Manual

11 NCK Commissioning with HMI Advanced
11.7 Digital and analog I/O devices
11.7.4

Digital input/output bytes and system variables

Digital inputs
Digital outputs
11-392
The following configuration example shows the relationship between digital in-
put bytes and system variables by means of the configuration of 3 digital inputs
bytes.
This configuration example requires the following:
– MCI board extension module: 1 input byte
– PROFIBUS DP signal modules: 2 input bytes
The MCI board extension module is always assigned to a digital input byte. Dig-
ital input bytes of external signal modules must therefore always be counted as
additional input bytes:
S
MD10350: FASTIO_DIG_NUM_INPUTS = 1 + m,
where m = number of inputs bytes of external signal modules
Because the 1st input byte is permanently assigned to the MCI board extension
module, only the input bytes of the external signal modules have to be explicitly
assigned to the system variables.
S
MD10366: HW_ASSIGN_DIG_FASTIN[0] –> 1st external input byte
S
MD10366: HW_ASSIGN_DIG_FASTIN[1] –> 2nd external input byte
MD10350: FASTIO_DIG_NUM_INPUTS = 3 = 1 + m
with: 1 –> 1st dig. input byte of the MCI board extension module
(always 1, see text)
m=2 –> 2nd and 3rd dig. input byte via PROFIBUS I/O
modules (number of input bytes used from
external signal modules)
MCI board ex. module
MD10366: HW_ASSIGN_DIG_FASTIN [n]
05
05
Fig. 11-31 Configuration example: 3 digital input bytes
If the optional MCI board extension module does not exist, assignment in the
machine data must still be made as stated because the 1st input byte is inter-
nally permanently assigned to this module. System variables $A_IN[1] to
$A_IN[4] do not then contain information.
Digital outputs must be configured as described above for digital inputs.
00 I/O high I/O low 0
00 I/O high I/O low 1
:
:
n
© Siemens AG 2007 All Rights Reserved
SINUMERIK 840Di sl Manual (HBIsl) – 01/2007 Edition
01/2007
System variable:
$A_IN[1] ... $A_IN[4]
$A_IN[9] ... $A_IN[16]
$A_IN[17] ... $A_IN[24]