Siemens SIMATIC S7-1200 - Page 862

Communication
11.2 PROFINET
S7-1200 Programmable controller
862 System Manual, V4.2, 09/2016, A5E02486680-AK
TSEND and TRCV
Note
When using PROFINET Open User commun
ication, if you execute a TSEND instruction
without a corresponding TRCV instruction executing on the remote device, then the TSEND
instruction may reside indefinitely in a "Busy State", waiting for the TRCV instruction to
receive the data. In this state,
the TSEND instruction "Busy" output is set, and the "Status"
output has a value of "0x7002". This condition may occur if you are transferring more than
4096 bytes of data. The issue is resolved at the next execution of the TRCV instruction.
Table 11- 23 TSEND and TRCV instructions
LAD / FBD
SCL
Description
"TSEND_DB"(
req:=_bool_in_,
ID:=_word_in_,
len:=_udint_in_,
done=>_bool_out_,
busy=>_bool_out_,
error=>_bool_out_,
status=>_word_out_,
data:=_variant_inout_);
TCP and ISO on TCP: TSEND sends data
through a communication connection from the
CPU to a partner station.
"TRCV_DB"(
en_r:=_bool_in_,
ID:=_word_in_,
len:=_udint_in_,
adhoc:=_bool_in_,
ndr=>_bool_out_,
busy=>_bool_out_,
error=>_bool_out_,
status=>_word_out_,
rcvd_len=>_udint_out_,
data:=_variant_inout_);
TCP and ISO on TCP: TRCV receives data
through a communication connection from a
partner station to the CPU.
1
STEP 7 automatically creates the DB when you insert the instruction.