80960JD datasheet(13/86 Pages) INTEL

13 / 86 page

80960JA/JF/JD/JS/JC/JT 3.3 V Embedded 32-Bit Microprocessor

Datasheet

The 80960Jx provides testability features compatible with IEEE Standard Test Access Port and

Boundary Scan Architecture (IEEE Std. 1149.1).

One of the boundary scan instructions, HIGHZ, forces the processor to float all its output pins

(ONCE mode). ONCE mode may also be initiated at reset without using the boundary scan

mechanism.

ONCE mode is useful for board-level testing. This feature allows a mounted 80960Jx to

electrically “remove” itself from a circuit board. This allows for system-level testing in which a

remote tester, such as an in-circuit emulator, may exercise the processor system.

The provided test logic does not interfere with component or circuit board behavior and ensures

that components function correctly, connections between various components are correct, and

various components interact correctly on the printed circuit board.

The JTAG Boundary Scan feature is an attractive alternative to conventional “bed-of-nails” testing.

It may examine connections that might otherwise be inaccessible to a test system.

2.9

Memory-Mapped Control Registers

The 80960Jx, although compliant with the i960 processor core, has the added advantage of

memory-mapped, internal control registers not found on the i960 Kx, Sx or Cx processors. These

registers give software the interface to easily read and modify internal control registers.

Each of these registers is accessed as a memory-mapped, 32-bit register. Access is accomplished

through regular memory-format instructions. The processor ensures that these accesses do not

generate external bus cycles.

2.10

Data Types and Memory Addressing Modes

As with all i960 processors, the 80960Jx instruction set supports several data types and formats:

• Bit

• Bit fields

• Integer (8-, 16-, 32-, 64-bit)

• Ordinal (8-, 16-, 32-, 64-bit unsigned integers)

• Triple word (96 bits)

• Quad word (128 bits)

The 80960Jx provides a full set of addressing modes for C and assembly programming:

• Two Absolute modes

• Five Register Indirect modes

• Index with displacement

• IP with displacement

80960JD Datasheet(PDF) 13 Page - Intel Corporation