Bus Interface Unit (Biu) - Siemens SIMATIC NET SPC 4-2 LF Manual

11.2

Bus Interface Unit (BIU)

Description
The bus interface unit provides the interface to the microcontroller. It allows the
connected microcontroller access to the internal 3-Kbyte dual port RAM.
Depending on the connected microcontroller types, the BIU generates the request
signals for the dual-port RAM controller from the control signals (ALE with internally
generated CS signal or E-clock rate with an externally applied CS signal.
PROFIBUS Controller SPC 4®-2 LF
C79000-G8976-C157-3
Processor Interface
133