Hitachi EH-150 Series Applications Manual page 51

(2) Modem line control
Specify whether the state of the control signal (RS, ER) is always set to high or switched by user program.
No. Set value
1 Hxx0x
2 Hxx1x
- Others
This setting is effective only when using the RS-232C port. When port1 or port 2 is used as RS-422/485, please
set "0".
Regardless of the above setting, RS and ER will be turned off automatically when an error occurs in EH-SIO and
receiving buffer is full.
(3) Data conversion type
EH-SIO has data conversion function. Specify the conversion type as below.
No. Set Value
1 Hxxx0
2 Hxxx1
3 Hxxx2
- Others
Through type (no conversion) :
The data stored in sending data area are transmitted as is, and the received data are stored in receiving data area
as is.
CPU module
H3031
H1234
H4142
HABCD
« Note »
 Caution is necessary when using a message composition with start/stop characters since those parts will be
considered as starting and stopping points.
 When using 7-bit transmission format configuration, the data of H80-HFF cannot be transmitted and received
correctly.
Table 6.3 Control list of registration modem lines
Modem line control
RS, ER always high
RS, ER follows the state of RS and ER flag of control register.
Initial setting error
Table 6.4 Registration data conversion type list
Data conversion type
Through (no conversion)
Binary / ASCII conversion (CPU / Binary  EH-SIO / ASCII)
Binary through (CPU / Binary  EH-SIO / Binary)
Initial setting error
EH-SIO
41 42 AB CD
Figure 6.9 Example of through type (no conversion)
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Chapter6 Communication Mode
External device
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