Siemens SIMATIC S7-200 System Manual page 312

S7-200 Programmable Controller System Manual
Special Memory Locations for the Position Module
The S7-200 allocates 50 bytes of special memory (SM) to each intelligent module, based on the
physical position of the module in the I/O system. See Table 9-23. When the module detects an
error condition or a change in status of the data, the module updates these SM locations. The first
module updates SMB200 through SMB249 as required to report the error condition, the second
module updates SMB250 through SMB299, and so on.
Table 9-23 Special Memory Bytes SMB200 to SMB549
SM Bytes for an intelligent module in:
Slot 0
SMB200 to SMB250 to
SMB249 SMB299
Table 9-24 shows the structure of the SM data area allocated for an intelligent module. The
definition is given as if this were the intelligent module is located in slot 0 of the I/O system.
Table 9-24 Special Memory Area Definition for the EM 253 Position Module
SM Address Description
SMB200 to Module name (16 ASCII characters). SMB200 is the first character: "EM253 Position"
SMB215
SMB216 to Software revision number (4 ASCII characters). SMB216 is the first character.
SMB219
SMW220 Error code for the module. See Table 9-21 for a description of the error codes.
SMB222 Input/output status. Reflects the
status of the inputs and outputs
of the module.
DIS
STP
LMT- -
LMT+
RPS
ZP
SMB223 Instantaneous module status. Reflects
the status of the module configuration
and rotation direction status.
OR Target speed out of range
R Direction of rotation
CFG Module configured
SMB224 CUR_PF is a byte that indicates the profile currently being executed.
SMB225 CUR_STP is a byte that indicates the step currently being executed in the profile.
SMD226 CUR_POS is a double-word value that indicates the current position of the module.
SMD230 CUR_SPD is a double-word value that indicates the current speed of the module.
SMB234 Result of the instruction. See Table 9-20 for
descriptions of the error codes. Error conditions
above 127 are generated by the instruction
subroutines created by the wizard.
D Done bit
SMB235 to Reserved
SMB244
SMB245 Offset to the first Q byte used as the command interface to this module. The offset is supplied by the
S7-200 automatically for the convenience of the user and is not needed by the module.
SMD246 Pointer to the V memory location of the configuration/profile table. A pointer value to an area other than
V memory is not valid. The Position module monitors this location until it receives a non-zero pointer
value.
298
Slot 1 Slot 2
SMB300 to
SMB349
Disable outputs
Stop input
Negative travel limit input
Positive travel limit input
Reference point switch input
Zero pulse input
0= Operation in progress
1= Operation complete (set by the module during initialization)
Slot 3 Slot 4
SMB350 to SMB400 to
SMB399 SMB449
MSB
7 6 5 4
DIS 0 0 STP
0 = No current flow
0 = No current flow
0 = No current flow
0 = No current flow
0 = No current flow
0 = No current flow
MSB
7 6 5 4
0 0 0 0
0 = In range
0 = Positive rotation
0 = Not configured
MSB
7 6
D
Slot 5 Slot 6
SMB450 to SMB500 to
SMB499 SMB549
LSB
3 2 1 0
LMT- - LMT+ RPS ZP
1 = Current flow
1 = Current flow
1 = Current flow
1 = Current flow
1 = Current flow
1 = Current flow
LSB
3 2 1 0
0 OR R CFG
1 = Out of range
1 = Negative rotation
1 = Configured
LSB
0
ERROR