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Theory of Operation
The Microprocessor Board
Microprocessor Board Theory
The microprocessor board contains the system memory, all of the interfaces for the mainframe peripherals, the intermodule bus monitor, and the option board module interface.
Microprocessor and System ROM & RAM
The processing engine of the HP 16500B microprocessor board is a Motorola 68EC030 microprocessor. The 68EC030 is supported by 128 Kbytes of ROM and 8 Mbytes of single inline memory module (SIMM) RAM. Stored in ROM are the
Supply Voltage Supervisor
The Supply Voltage Supervisor (SVS) monitors the main power supply bus and ensures a smooth
During
Interrupt Control
The Interrupt Control circuit manages the interrupt signals asserted by the peripheral devices. When an interrupt is received, the Interrupt Control circuit encodes the interrupt signal from the peripheral device to the microprocessor as a prioritized microprocessor interrupt.
Address Area Decoder and Peripheral Decoder
The mainframe peripheral interfaces link the microprocessor data and address busses with the system peripherals. The system peripherals are then selected by the microprocessor through the address area decoder and peripheral decoder. The peripheral decoder selects all peripherals including the HIL interface, the
Real Time Clock
The Real Time Clock provides time information to the HP 16500B microprocessor system. The time information is used to place a time stamp on files stored on both the hard and flexible disk drives. Time information may also be used by certain option modules to time stamp acquired data. For more information regarding the option modules, refer to the User’s Guide of the specific module.
Ethernet LAN Interface
Using line drivers, the Ethernet LAN Interface links the microprocessor address and data bus with the LAN controller IC on the HP 16500L Interface Module. Consult the HP 16500L Administrator’s and Service Guide for more information regarding the HP 16500L Interface Module.