MA28155

MA28155 MA28155 Radiation Hard Programmable Peripheral Interface Replaces June 1999 version, DS3575-4.0 DS3575-5.0 January 2000 The MA28155 is a general purpose programmable Input/ Output device designed for use with the MAS281 microprocessor. It has 24 I/O pins which may be individually programmed in 2 groups of 12 and used in 3 major modes of operation. In the first mode (MODE 0), each group of 12 I/O pins may be programmed in sets of 4 to be inputs or outputs. In the second mode (MODE 1), each group may be programmed to have 8 lines of input or output. Of the remaining 4 pins, 3 are used for hand-shaking and interrupt control signals. The third mode of operation (MODE 2) is the bidirectional bus mode, which uses 8 lines for a bidirectional bus and 5 lines, borrowing one from the other group, for hand-shaking. FEATURES s Radiation Hard to 1MRad (Si) s High SEU Immunity, Latch Up Free s Silicon-on-Sapphire Technology s 24 Programmable l/O Pins s All Inputs and Outputs are TTL Compatible s Direct Bit Set/Reset Capability Easing Control Application Interface s Replaces Several MSI Packages s Compatible with MAS281 (Mil-Std-1750A) Microprocessor RD/WN DSN CSN Figure 1: Block Diagram 1/20 MA28155 FUNCTIONAL DESCRIPTION The MA28155 is a programmable peripheral interface (PPI) device designed for use with MAS281. Its function is that of a general purpose l/O component to interface peripheral equipment to the microcomputer system bus. The functional configuration of the MA2...