IDEC FC4A-C10R2, User Manual

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As described above, when start internal relay M8050 is turned on, the initialization string is sent, followed by the ATZ
command and the dial command. When start internal relay M8051 is turned on, the ATZ command is sent, followed by the
dial command. The dial command can also be sent separately by turning on start internal relay M8052.
If retry cycles are set to data register D8109, the dial command is repeated at retry intervals specified by D8110 (default 90
seconds) as many as the specified retry cycles (default 3 cycles) until the telephone line is connected.
When the dial command has been completed successfully, internal relay M8062 is turned on. If the dial command fails,
internal relay M8072 is turned on.
The dial command is determined successful when the DCD signal is turned on.
Note: When the
MicroSmart
is powered down while the telephone line is connected, the telephone line is disconnected
because the DTR signal is turned off. This method should not be used for disconnecting the telephone line. Always use
M8053 to disconnect the telephone line as described below.
RS232C Port Communication Protocol
Before the telephone line is connected in the modem mode after power-up, the RS232C port 2 can only send out an AT
command by turning on a start internal relay M8050-M8056. The communication protocol for the RS232C port 2 after the
telephone line is connected is selected by the value stored in data register D8103.
When the telephone line is disconnected, the RS232C port 2 restores the state as before the telephone line was connected,
whether D8103 is set to 0 or 1.
When using a TXD or RXD instruction in the user communication mode while the telephone line is connected, insert
internal relay M8077 (line connection) as an input condition for the TXD or RXD instruction. After the telephone line is
connected, make sure of an approximately 1-second interval before executing the TXD or RXD instruction until the tele-
phone line connection stabilizes.
Note: When the MicroSmart is stopped while the telephone line is connected, the RS232C por t 2 protocol changes to the
maintenance protocol even if D8103 is set to 1 (user protocol in the on-line mode); then the telephone line remains con-
nected. When the
MicroSmart is restar ted, the user protocol is enabled again.
Disconnect Mode
The disconnect mode includes only one command to disconnect the telephone line. To disconnect the telephone line, turn
on internal relay M8053. The telephone line is disconnected by turning off the DTR signal since the initialization string
includes the &D2 command.
While a modem command is executed, another command cannot be executed. If two or more start internal relays are
turned on simultaneously, an error will result and error code 61 is stored in modem mode status data register D8111 (see
page 27-7).
When the disconnect command has been completed successfully, internal relay M8063 is turned on. If the disconnect com-
mand fails, internal relay M8073 is turned on.
The disconnect command is determined successful when the DCD signal is turned off.
After the telephone line is disconnected, the RS232C port 2 restores the state as before the telephone line was connected
whether D8103 is set to 0 or 1 so that the RS232C port 2 can be controlled by turning on a start internal relay M8050-
M8056.
AT General Command Mode
Data registers D8130-D8144 are allocated to the AT command string. Before turning on start internal relay M8054 for the
AT general command mode, store an AT command string in data registers starting with D8130. One data register stores
two characters: the first character at the upper byte and the second character at the lower byte in the data register. Use the
MOV (move) instructions on
WindLDR
to set the AT command string and execute the MOV instructions before turning
M8054 on.
D8103 Value RS232C Port 2 Communication Protocol in the On-Line Mode
0 (other than 1) Maintenance protocol
1 User protocol