Celestron 21020 통신 프로토콜 매뉴얼 - 페이지 8

{카테고리_이름} Celestron 21020에 대한 통신 프로토콜 매뉴얼을 온라인으로 검색하거나 PDF를 다운로드하세요. Celestron 21020 8 페이지. Nexstar hand control

페이지 인쇄

Get Device Version

Devices include:

16 = AZM/RA Motor

17 = ALT/DEC Motor

176 = GPS Unit

178 = RTC (CGE only)

Get Model

1 = GPS Series

3 = i-Series

4 = i-Series SE

5 = CGE

6 = Advanced GT

7 = SLT

9 = CPC

10 = GT

11 = 4/5 SE

12 = 6/8 SE

Echo

- useful to check

communication

Is Alignment Complete?

- align=1 if aligned and

0 if not

Is GOTO in Progress?

- Response is ASCII "0"

or "1"

Cancel GOTO

Developer Notes

Timeouts

If the hand control is sent a command that requires it to communicate with another device, then the hand control will

make multiple attempts to get the message through in the event of communications problems. Examples include "Get

Position" commands, "GOTO in Progress" commands, etc.

Software drivers should be prepared to wait up to 3.5s (worst case scenario) for a hand control response. If serial

commands are "blindly" sent without waiting for a response, then some commands may be dropped or the software

driver could see responses that are for earlier commands.

Pass-through Commands with No Response

Commands that start with 'P' are special pass-through commands that communicate with a specific telescope device.

For instance, the Slew commands talk directly to the motor control. If a 'P' command is sent but no response is

returned (because the device is not there or the command is unknown or there was a communication problem) then one

extra data byte is returned before the '#' terminating character and any returned data is garbage. This is done to give

software drivers a flag that something went wrong so appropriate action can be taken. It is particularly useful if you

want to check for the existence of a device: for instance, check the time from the GPS unit, and look for an error

response. Software drivers should check for the '#' termination character and if it is a different character then the next

character (hopefully '#') should be consumed and any command-specific handling should be done.

"P" &

chr(major) &

chr(1) &

chr(minor) &

chr(dev) &

"#"

chr(254) &

chr(0) &

chr(2)

"m"

chr(model) &

"#"

"K" &

chr(x) & "#"

chr(x)

"J"

chr(align) &

"L"

prog & "#"

"M"

"#"

1.6+

2.2+

1.2+