
B--65245EN/02
4. DIRECT COMMANDSHANDLING
107
Direct commands are classified into two types: instruction commands
which are sent from the host to a servo amplifier unit, and response
commands which are returned from a servo amplifier unit t o the host.
Such command transfer is controlled using two flags, control flag 1 and
control flag 2. Control flag 1 is sent from the host to a servo amplifier unit.
Control flag 2 is returned from a servo amplifier unit to t he host.
#7 #6 #5 #4 #3 #2 #1 #0
EBUF EOREND ECNT
Control flag 1
EBSY EOSTB E CF USR1 EOPC AL ECONT
Control flag 2
CAUTION
When the power mate CNC manager function is used,
control flag 2 transfers data using the same area as that
used by the power mate CNC manager function,
simultaneously as the function. If the USR1 signal is 0,
control flag 2 is for the ladder. If the USR1 signal is 1, control
flag 2 is for the power mate CNC manager and, therefore,
must be ignored.
Instruction commands sent from the host to a servo amplifier unit are
controlled with EBUF and EBSY.
When the EBUF and EBSY states (values) match, the host can write a
command into the interface area. After writing the command, the host
inverts EBUF.
If the EBUF and EBSY states differ, the servo amplifier unit assumes that
a new command has been specified.
Therefore, control flag 1
must be written last after a function number
and command data are written. After the servo amplifier unit reads the
command, it inverts the EBS Y state.
EBUF is initially set to 0.
Since the instruction command data area is limited, instruction command
data sometimes cannot be sent if the amount of data is excessive. In such
a case, more than one instruction command must be issued to send all the
data. If there is an additional instruction command to be sent, ECNT is
set to 1 to indicate that another command follows.
NOTE
When the power mate CNC manager function is used, the
inverted EBSY state is posted to the host for 40 ms. This
duration can be changed by parameter setting (parameter
No. 022).
4.2
DIRECT COMMAND
CONTROL
PROCEDURE
4.2.1
Direct Command
Control Procedure
4.2.2
Instruction Command
Control (EBUF, EBSY,
and ECNT)