PC11 High-Speed Paper-Tape Reader/Punch Control

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The PC11 is the UNIBUS device controller for the PC05 paper tape high-speed reader/punch. It uses programmed I/O, with interrupts when it is ready for/with more data.

There are two versions, both of which plug into an SPC slot. The first is a dual card, the M781, which is used with an M105 Address Selector and an M782 Interrupt Control (both tall singles). The second is a single quad board, the M7810.

A pair of cables (one for the reader, one for the punch - to support reader-only or punch-only options) connect it to the device. The cables are different between the two versions of the PC11; the first has H807 connectors on the side of the card into which small PCBs with plated contact fingers plug; the second version uses a pair of female-shell/male-pin Berg connectors.

Registers

The two versions are programming-compatible. The device has four control registers, which can be configured to any four sequential word locations in the I/O page; it is normally configured to addresses 777550-777556:

Register Abbreviation Address
Paper-Tape Reader Status Register PRS 777550
Paper-Tape Reader Buffer Register PRB 777552
Paper-Tape Punch Status Register PPS 777554
Paper-Tape Punch Buffer Register PPB 777556

In the register contents (below), bits which are read/write or unused are shown in normal font, those which are read-only are in italics, and write-only in bold.

Reader Status Register (PRS)

ERR Unused BUSY Unused DONE INT ENB Unused RDR ENB
15 14 13 12 11 10 09 08 07 06 05 04 03 02 01 00

Reader Buffer Register (PRB)

Unused Input Data
15 14 13 12 11 10 09 08 07 06 05 04 03 02 01 00

Punch Status Register (PPS)

ERR Unused RDY INT ENB Unused
15 14 13 12 11 10 09 08 07 06 05 04 03 02 01 00

Punch Buffer Register (PPB)

Unused Output Data
15 14 13 12 11 10 09 08 07 06 05 04 03 02 01 00

The PPB does not respond to 'read' cycles on the UNIBUS.