turck BL20 - Page 246

BL20 - Communication in CANopen
D301087 0308 - BL20 CANopen4-174
Table 109:
Meaning of the
data bits for
RS232/485-
modules
Designation Value Description
STATRES 0-1 The STATRES bit is used for resetting
the STAT bit of the process input data
(object 5601
hex
)
The STAT bit is reset (from 0 to 1) with
the transition from 1 to 0 (falling
edge).
If this bit is 0, all changes in the data
fields TX_BYTE_CNT, TX_CNT and
RX_CNT_ACK are ignored. The
clearing of the receive and transmit
buffer by RXBUF FLUSH/TXBUF
FLUSH is possible.
The value 1 or the transition from 0 to
1 disables the clearing of the receive
and transmit buffer by the
RXBUF FLUSH/TXBUF FLUSH.
RX_CNT_ACK 0-3 The value RX_CNT_ACK is a copy of
the value RX_CNT. The value
RX_CNT was transferred together
with the last data segment of the
process input data (object 5601
hex
).
The value RX_CNT_ACK is a confir-
mation of successful acceptance of
the data segment using RX_CNT.
TX_CNT 0-3 The value TX_CNT is transferred
together with every data segment of
the process output data. The
sequence of the TX_CNT values is:
00 -> 01 -> 10 -> 11 -> 00...
(decimal: 0 -> 1 -> 2 -> 3 -> 0...)
A faulty sequence indicates that data
segments are missing.
TX_BYTE_CNT 0-7 Number of valid user data bytes in
this data segment.