Plug the small, rounded end of the RS-232 cable into the DIN socket labelled “RS-232” in the back of your HX-20. Then plug the other end of the cable into the corresponding socket on your RS-232 device.

Now the HX-20 and the RS-232 device are connected. In order for them to communicate, however, they must share a common protocol. Two devices may be connected electrically, but never communicate properly, if they don’t share a common communications protocol. Try to configure your RS-232 device so that it will be compatible with the initial or default protocol of the HX-20, as defined in Table 6-2.

TABLE 6-2

HX-20 Default Protocol for RS-232 Port

Data

rate:

 

 

4800 Baud

 

Word length:

 

8 bits

 

Parity:

 

 

none

 

Stop

bits:

 

 

2

 

CD

(Carrier Detect):

ignored

 

RTS (Request to Send): held “high” by HX-20

DSR

(Data

Set

Ready):

controlled by

external

 

 

 

 

device; “high”

means

 

 

 

 

HX-20 may transmit

 

 

 

 

data; “low” causes HX-20

 

 

 

 

to wait

 

CTS

(Clear

to

Send):

ignored

 

If you configure the RS-232 device according to this protocol, you will find it very easy to transmit text and data to the device. However, by using appropriate parameters with the OPEN statement, you can command the HX-20 to use any desired proto- col. (See the Epson HX-20 BASIC Tutorial and Reference Manual.)

Connecting your HX-20 to a bar code reader

On the right side of your HX-20, you will notice a socket marked “BAR CODE.”

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