|
Software
Installation
53
5
6
3
Receive
data
The
RS
‐
485’s
operation
of
receiving
data
is
in
the
same
of
the
RS
‐
232’s.
5
6
4
Basic
Language
Example
a.
Initial
86C450
UART
10
OPEN
“COM1:9600,m,8,1”AS
#1
LEN=1
20
REM
Reset
DTR
30
OUT
&H3FC,
(INP(%H3FC)
AND
&HFA)
40
RETURN
b.
Send
out
one
character
to
COM1
10
REM
Enabled
transmitter
by
setting
DTR
ON
20
OUT
&H3FC,
(INP(&H3FC)
OR
&H01)
30
REM
Send
out
one
character
40
#1,
OUTCHR$
50
REM
Check
transmitter
holding
register
and
shift
register
60
IF
((INP(&H3FD)
AND
&H60)
>0)
THEN
60
70
REM
Disabled
transmitter
by
resetting
DTR
80
OUT
&H3FC,
(INP(&H3FC)
AND
&HEF)
90
RETURN
c. Receive one character from COM1
10
REM
Check
COM1:
receiver
buffer
20
IF
LOF(1)<256
THEN
70
30
REM
Receiver
buffer
is
empty
40
INPSTR$”
50
RETURN
60
REM
Read
one
character
from
COM1:
buffer
70
INPSTR$=INPUT$(1,#1)
80
RETURN
Note
10:
The
RS
‐
485
of
the
JetBox
uses
COM1.
If
you
want
to
program
it
and
hardware
setup,
please
refer
to
the
BIOS
Setup
for
COM1
address
setup
and
the
