Baader Planetarium Steeldrive II, Technical Documentation Manual

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Chapter 3
Communication Protocol
3.1 Virtual COM-Port Configuration
Parameter Value
baudrate 19200
bytesize 8 bit
parity bit none
stop bit one
timeout 0.1s
conoff false
rtscts false
dsrdtr false
Always append CR+LF.
Settings for the RS232 terminal programm Termite
3.1.1 Communication protocol
All characters send to the device will be echoed. This provides an simple way to verifiy the device
receives complete messages.
•
The device will ignore all essages not starting with the prefix ”$BS”.
•
The communication of the device with the digital temperature sensors involves some blocking
operations (up to 500
µs ). During this period there is a chance that some characters will be
missed. Once the device receives any serial communication, it will only communicate with the
sensors just before answering to valid serial commands. This is intended for periodically polling
(say 1-2 Hz). If there is no serial communication for 10s, the device will poll the sensors every
second.
•
CRC checksum verification of the communication is not mandatory but encouraged (see 3.2.5 ).
•
On boot, the device will send:
$BS Hello World!\ r \n
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