Changing Sensor Type (Afm1540 Only); Smb Interface (Serial Measurement Bus, Afm1540 Only) - ECM AFM1040 Instruction Manual

Changing Sensor Type (AFM1540 Only)

AFMs are delivered programmed to use one of the following sensors: Bosch LSU 4.9, LSU
4.2, or NTK UEGO. This is indicated on the AFM's label. The AFM1540 can be user-
reprogrammed to use any one of these sensors. PC software routine AFM1540.EXE is
supplied with the AFM1540 to facilitate this. Refer to the Supplementary Information
section at the end of this manual for more information.

SMB Interface (Serial Measurement Bus, AFM1540 Only)

The AFM1540 has a SMB interface allowing serial communication with as many as 16
AFM1540 modules using a single RS-232 type serial port from a computer. Using the SMB
interface, AFR, FAR (the inverse of AFR), λ, %O , and module status can be read from each
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AFM1540 module. The interface supports auto-detection of modules.
The figure below shows an example with three AFM1540 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 AFM1540.
Cable part number 1500A-16 connects the PC to the SMB/PC port of any one of the
AFM1540 modules (i.e. it does not have to be the module with address 0), and subsequent
AFM1540 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).
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