Siemens Simatic S7-400 - Page 101

Event Class 8 (08H): "Receive error"
Event No. Event To correct or avoid errors
(08)01H With 3964(R) only:
Expecting the 󹪝rst repetition:
An error was recognized on receiving a telegram and
the CP requested repetition from the partner via a
negative acknowledgment (NAK).
A repetition is not an error, however, it can be an indi‐
cation that there are disturbances on the transmission
line or a malfunction of the partner device. If the mes‐
sage frame has still not been transmitted after the
maximum number of repetitions, an error number de‐
scribing the 󹪝rst error that occurred is output.
(08)02H With 3964(R) only:
Error during connection setup:
• In idle mode, one or more random codes (other
than NAK or STX) were received, or
• after an STX was received, partner sent more co‐
des without waiting for response DLE.
After the partner has signaled POWER ON:
• While partner is being activated, CP receives an
unde󹪝ned code.
Identify the malfunction on the partner device, possi‐
bly by using an interface test device is switched into
the transmission line.
(08)05H With 3964(R) only:
Logical error during receiving:
After DLE was received, a further random code (oth‐
er than DLE or ETX) was received.
Check if partner DLE in message frame header and in
data string is always in duplicate or the connection is
released with DLE ETX. Identify the malfunction on the
partner device, possibly by using an interface test de‐
vice is switched into the transmission line.
(08)06H Character delay time exceeded:
• Two successive characters were not received
within character delay time, or
With 3964(R) only:
• 1. character after sending of DLE during connec‐
tion setup was not received within character de‐
lay time.
Partner device faulty or too slow. Identify the malfunc‐
tion, possibly by using an interface test device switch‐
ed into the transmission line.
(08)07H Impermissible message frame length:
A message frame of length 0 was received.
Receipt of a message frame of length 0 is not an error.
Check why the communication partner is sending
message frames without user data.
(08)08H With 3964(R) only:
Error in block check character (BCC)
Internally calculated value of BCC does not match
BCC received by partner at end of connection.
Check whether connection is badly damaged; in this
case you may also occasionally see error codes. Iden‐
tify the malfunction on the partner device, possibly by
using an interface test device is switched into the
transmission line.
(08)09H With 3964(R) only:
Waiting time for block repetition has expired
Con󹪝gure the same block wait time in the communi‐
cation partner as for the CP 440. Identify the malfunc‐
tion in the communication partner, possibly by using
an interface test device switched into the transmission
line.
(08)0AH There is no free receive bu󹪜er available:
No empty receive bu󹪜er was available to receive da‐
ta.
The RECV_440 FB must be called more frequently.
Diagnostics with the CP 440
8.3 Diagnostics Messages of the Function Blocks
Point-to-point connection CP 440 Installation and Parameter Assignment
Equipment Manual, 03/2022, A5E00057742-AE 101