Intel KU82303-20

The Intel 82303 combines Micro Channel card setup, parallel-port logic, peripheral-bus address latches and motherboard setup support. Intel describes it as a companion to the 82304 local I/O support chip and 82077 floppy-disk controller in Micro Channel-compatible systems. It is not a standalone CPU, floppy controller or general-purpose modern parallel-port controller.

• Integrates a standard or bidirectional extended-mode parallel port.
• Provides the Micro Channel Card Setup Port at address 96h.
• Latches address and selected decode signals for a peripheral bus.
• Supports motherboard setup ports and resets.
• Reduces discrete logic in the documented Intel chipset context.

The bus interface accepts unlatched Micro Channel address signals and provides latched peripheral-bus address outputs. The parallel-port block supports normal and bidirectional extended operation; external connector drivers remain necessary. The setup block produces individual card setup selects and a software-initiated reset. Motherboard support includes decoded strobes for setup ports 101h and 103h. Consult IBM and Intel programming references for register-level behavior.

Intel's 82303 family document states a 100-pin plastic quad flat package. The catalog field says 100-QFP, while one Rochester/DigiKey listing describes 100-PQFP. The precise local register mapping and exact KU82303-20 mechanical variant remain unverified. The candidate 100-QFP JPG is not present locally. Validate pin-one orientation, outline dimensions and lead pitch from a controlled drawing before assembly.

Assembly checks

• Check all gull-wing leads and body dimensions.
• Confirm pin-one location against the Intel drawing.
• Compare solder footprint with the actual supplied lot.

The Intel signal table groups A[0:2,10:23] Micro Channel address inputs, XA[0:2,10:23] latched peripheral-bus address outputs and bidirectional XD[0:7] data. IOR#, IOW#, MIO# and ADL# qualify bus activity. The parallel port has STROBE, AUTOFC, SLCTIN, INIT, ACK#, BUSY and ERROR# functions. Card setup uses CDSU# selects and associated strobes. Use the numbered Intel pin table for wiring; this summary is not a pin-number map.

These supply and temperature values describe the family data-sheet test conditions; confirm exact KU82303-20 ordering and board timing before applying them to a lot.

No internal alternate is linked or qualified. Other 82303 speed or package codes must not be assumed interchangeable. Check the exact suffix, supply, timing, footprint, firmware register usage and connector-driver circuit before replacing an existing chip.

Intel authored the 82303 Local I/O Support Chip data sheet, order number 290184-001, dated November 1988, documenting the functional blocks, signals and 100-pin package. This archival family source is stronger for technical behavior than current reseller summaries, but the precise KU82303-20 ordering code needs separate manufacturer or controlled lot confirmation.

• Maintenance of Micro Channel-compatible motherboards.
• Legacy parallel-port and card-setup circuitry.
• Qualified systems using the 82303/82304/82077 peripheral chipset.

Inspect full Intel and speed-grade markings, date code, lead condition and original supply documentation. The catalog lists 1,045 units at USD 40.00, minimum seven, without tier pricing. A DigiKey/Rochester exact-code index shows 1,045 units, MOQ six and about USD 49.23 at quantity ten; this is an indexed rather than a dated checkout quote. Commercial terms differ and were not updated. Obtain current supplier confirmation before release.

Keep this listing in manual review and noindex. Verify KU82303-20 order-code characteristics, exact 100-pin mechanical drawing and local package register; restore a verified JPG; and reconcile current stock, MOQ and price with a dated supplier quote. Do not publish until all evidence and page checks pass.