ECM afm1000, Инструкция по эксплуатации

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SMB Interface (Serial Measurement Bus, AFM1500 Only)
The AFM1500 has a SMB interface allowing serial communication with as many as 16
AFM1500 modules using a single RS-232 type serial port from a computer. Using the SMB
interface, AFR, FAR (the inverse of AFR), Lambda, %O
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, and module status can be read
from each AFM1500 module. The interface supports auto-detection of modules.
The figure below shows an example with three AFM1500 modules connected to a computer
(here a PC) using the SMB interface. Each module must have a unique address between 0
and Fh (i.e. 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E, F) that is set using a switch located
between the two SMB connectors on the AFM1500.
Cable part number 1500A-16 connects the PC to the SMB/PC port of any one of the
AFM1500 modules (i.e. it does not have to be the module with address 0), and subsequent
AFM1500 modules are daisy-chained using part number 1500A-17 cables.
Communication is 38400 baud, 1 stop bit, 8 data bits, 1 stop bit and no parity.
The computer sends a one byte message. The high nibble contains the module address (0 to
Fh) and the low nibble contains the command (0 to Fh).
The AFM1500 module addressed responds (within 1 ms max.) with the byte of data
requested.
The command from the PC to the AFM1500 modules and the conversion formulas for the
data from the AFM1500 modules to the PC are given in the following table. The state
diagram for SMB communication is at the back of this instruction manual.
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