65
A
A
p
p
p
p
e
e
n
n
d
d
i
i
x
x
D
D
-
-
R
R
S
S
-
-
2
2
3
3
2
2
C
C
o
o
n
n
n
n
e
e
c
c
t
t
i
i
o
o
n
n
(
(
f
f
o
o
r
r
C
C
o
o
m
m
p
p
u
u
t
t
e
e
r
r
i
i
z
z
e
e
d
d
H
H
a
a
n
n
d
d
C
C
o
o
n
n
t
t
r
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o
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l
l
)
)
You can control your NexStar telescope with a computer via the RS-232 port on the computerized hand
control and using an optional RS-232 cable (#93920). Once connected, the NexStar can be controlled using
popular astronomy software programs.
Communication Protocol:
NexStar-i communicates at 9600 bits/sec, No parity and a stop bit. All angles are communicated with 16 bit
angle and communicated using ASCII hexadecimal.
Description
PC Command ASCII
Hand Control Response
Notes
Echo
Kx
X#
Useful to check communication
Goto Azm-Alt
B12AB, 4000
#
10 characters sent. B=Command,
12AB=Azm, comma, 4000=Alt. If
command conflicts with slew limits,
there will be no action.
Goto Ra-Dec
R34AB, 12CE
#
Scope must be aligned. If
command conflicts with slew limits,
there will be no action.
Get Azm-Alt
Z
12AB, 4000#
10 characters returned,
12AB=Azm, comma, 4000=Alt, #
Get RA-Dec
E
34AB, 12CE#
Scope must be aligned
Cancel Goto
M
#
Is Goto in Progress
L
0# or 1#
0=No, 1=Yes; "0" is ASCII
character zero
Is Alignment Complete
J
0# or 1#
0=No, 1=Yes
Commands below available
on version 1.6 or later
HC version
V
1 6 #
Version 1.6
Stop/Start Tracking
Tx
x = 0 (Tracking off)
x = 1 (Alt-Az on)
x = 2 (EQ-N)
x = 3 (EQ-S)
#
Alt-Az tracking requires alignment
32-bit goto RA-Dec
r34AB0500,12CE0500
#
32-bit get RA-Dec
e
34AB0500,12CE0500#
The last two characters will always
be zero.
32-bit goto Azm-Alt
b34AB0500,12CE0500
#
32-bit get Azm-Alt
z
34AB0500,12CE0500#
The last two characters will always
be zero.
The cable required to interface to the telescope
has an RS-232 male plug at one end and a 4-4
telephone jack at the other end. The wiring is
as follows:
