Siemens 500 NIM - Manual (Page 90)

NIM Primitives 4-37 SIMATIC TIWAY I Series 500 NIM User Manual
Availability: Releases 1.1, 2.1, 2.2, and 3.0
Primitive 20 is a command to read a single contiguous block of data in the
Secondary device. Read Block will access contiguous data element locations
from a given data element location.
Request: LLLL 20 TT NNNN AAAA
Symbol Value Definition
TT Data element type
NNNN Number of locations
AAAA Data element location
Response: LLLL 20 HH DD ... DD
(repeated)
Symbol Value Definition
HH Attached device operational status
DD Data
Read Block
Primitive – Code 20