Thermo Scientific Micro-Tech 9101, Справочное руководство

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C-6 Micro-Tech 9101/9201 Reference Manual, Rev J Thermo Fisher Scientific
The communication protocol allows a remote intelligent device to read and
eventually write the contents of the registers, as listed in this section.
During the communication activity, the Micro-Tech always acts as Slave,
meaning that it will respond to a request from a Master device on the line,
but never attempts to send messages out.
The instrument responds only if the message is completely received. The
instrument reads the message and looks for the address, which is contained
in an address byte in the query package. The message is then processed
only if the address contained in the message matches the address specified
in the set-up data of the instrument. When the system receives a message,
the integrity of it is checked, and an answer message is prepared, if Yes.
The Master must respect a 100 ms interval time between two messages. If a
message is sent before 100 ms have passed since the previous one, it is lost.
(The data is received by an interrupt routine, while it is processed in a task
that is executed each 100 ms.)
If the Master sends variables to be written in memory, the system checks
the correctness of the message, and immediately sends an answer message,
if it is correct. This does not necessarily mean that the data is written in
memory. The system first checks the address, which must correspond to a
valid address of a variable, then the minimum and maximum limits are
checked, and then the password. If data can be accepted, the success flag is
set to 0 (no error), if not, it is set to 1. The Master needs to check the
success flag (contained into a read-only register), to know if the last
variables sent have been stored or not.
The procedure is as follows.

Send the data to the Micro-Tech.

Wait 100 ms.

Read the success flag, should be 0.
Some data is read only, some is read write, some is write only.
NOTE.
The maximum number of words the system can transfer is 41 per
time. Requests of registers in excess of 41 are treated as errors and do not
generate an answer.

Master/Slave
Interactions