IC-MB3 Datasheet, PDF (2/26 Pages) IC-Haus GmbH – BiSS INTERFACE MASTER, 1-Chan./3-Slaves

iC-MB3
BiSS INTERFACE MASTER, 1-Chan./3-Slaves
Rev D1, Page 2/26
DESCRIPTION
iC-MB3 is a single-chip BiSS/SSI interface controller
featuring an 8-bit bus interface to industrial standard
microcontrollers. An additional SPI interface mode
also enables serial communication between iC-MB3
and the connected microcontroller.
One to three BiSS devices can be attached to the
sensor side of the device. These are connected up to
clock line MA1 and data return line SL1 using RS422
transceivers (Figure 1). The BiSS devices can be con-
nected directly in noise-free environments.
A maximum of three BiSS slaves is supported, each
with their own independently scalable data sections
encompassing:
1) Sensor data from 0 to 64 bits
(for measurement data, alarms and warnings)
2) Register data with 128 bytes per slave ID
(e.g. for device parameters).
iC-MB3 provides dual RAM memory banks for each
slave, enabling flexible access of the microcontroller
while new sensor data is being read in. A 32-byte
intermediate memory supports register transfers.
Sensor data acquisition is started by a microcontroller
command or via pin GETSENS. Alternatively, iC-MB3
can also read in new sensor data automatically; the
cycle time in this instance can be set as required.
The end of sensor data acquisition and readin is sig-
naled at pin EOT by a high; if faults occur during
transmission pin NER signals a low. Errors in commu-
nication can be verified by the microcontroller via a
status register; a system error message can also enter
this register if bidirectional message pin NER is kept
low by external intervention.
iC-MB3 generates a clock signal for sensor communi-
cation using an internal 20 MHz oscillator. The clock
can also be supplied externally.
Figure 1: Point-to-point connection of iC-
Figure 2: Example network of iC-MB3 and three subscribers. All
MB3 and one bus subscriber. This can use 1 8 possible slave IDs (SIDs) are used distributed.
to 8 slave IDs (SID).