IBM 3745 Series, Hardware Maintenance Reference

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Serial Link (SL)
A serial link interconnects a LIC board and a scanner unit via MUX and CSC cards.
Communication Scanner Processor (CSP)
The communication scanner processor (CSP) operates under the control of the scanner microcode loaded
from the hard disk drive or diskette drive into CSP storage during IML.
The CSP is located on the communication scanner card (CSC).
Components
As shown on the next data flow the CSP:
(A) Connects to the IOC bus to receive or transmit data and controls
(B) Executes the instructions of the microcode to transmit and receive data, supports the link protocols,
translates characters, and controls the communication interface.
(C) Stores the microcode, the transmitted/received data, the line interface parameters, and the diagnos-
tics
(D) Provides registers in local storage for current CSP operation and permanent code in the ROS to
start the microcode IPL.
(E) Controls the storage and manages (by hardware only) the cycle steal with the FESL.
(F) Controls the CSP interrupts.
(G) Provides control storage address compare, and generates a CSP interrupt when the selected
address is encountered.
(H) Detects and reports the CSP errors via the CSP error register.
(I) Generates clocking signals to the processor, to the FESL and their associated logic from the basic
49.152 MHz clock.
Chapter 4. Transmission Subsystem (TSS)
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