Omron CJ1W-SCU32 Operation Manual page 166

4 Using Protocol Macros
Device vari-
Name able for CJ-
series Unit
Hardware *_P1_HwSetSt
Settings a
*_P2_HwSetSt
a
* The flags will also be initialized at the following times: when the Controller is reset, when the operating mode is
changed between PROGRAM and RUN Modes, when the Unit is restarted, or when the communications port is
restarted. After the variable is set, the status area will be reset (cleared) at the timing indicated in "Reset" in the
above table for each area.
Additional Information
With the protocol macros, each port has a reception buffer that will hold 2.5 KB max. The Unit
can use the reception buffer to hold a large quantity of data when it is received at once, or when
the communications sequence is in Wait status.
If the Unit receives data when the reception buffer is full, the receive data will overwrite the
2.5 KB of previously received data in the buffer. Therefore, always use flow control when the Unit
receives a large amount of data in Protocol Macro Mode.
4-30
Meaning
The following are read in port setting sta-
tus:
1. The serial communications modes and
communications specifications set in
the Setup Area (*_P1_PortCfg and
*_P2_PortCfg)
2. The ports and the terminating resis-
tance hardware settings
3. System settings errors, and Port Oper-
ating/Stopped Flags
In Protocol Macro Mode, the port will be
stopped if a protocol data error occurs
while protocol data is transferred.
If there is no protocol data error after the
protocol data has been transferred, the
flag will be changed to TRUE.
CJ-series Serial Communications Units Operation Manual for NJ-series CPU Unit(W494)
Timing
Initialize Set
Controller When status
reset (*) is read
Reset
When the
error is
cleared after
protocol data
is resent