CR11 Controller

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The CR11 Controller was a UNIBUS device controller for the CR11 Card Readers. It was a quad format card (M8290), and used an SPC slot; it used programmed I/O.

Registers

The device has three control and buffer registers, which can be configured to any three sequential word locations in the I/O page; it is normally configured to addresses 777160-777164:

Register Abbreviation Address
Status Register CRS 777160
Data Buffer Register CRB1 777162
Data Buffer Register Encoded Output CRB2 777164

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.

Status Register (CRS)

ERR CARD DONE SUPP ERR RDR CHECK TIM ERR RDR ONL BUSY RDR RDY COL RDY INT ENB Unused EJECT READ
15 14 13 12 11 10 09 08 07 06 05 04 03 02 01 00

Data Buffer Register (CRB1)

Unused Zones 12-10 Zones 1-9
15 14 13 12 11 10 09 08 07 06 05 04 03 02 01 00

Data Buffer Register - Encoded Output (CRB2)

Unused Zones 12-8 Encoded Zones 1-7
15 14 13 12 11 10 09 08 07 06 05 04 03 02 01 00

The first buffer register is 12-bit raw data from the card, the second is the compressed Hollerith code (zones 1-7 can have only a single punch, which is encoded in octal in 3 bits; a '0' means 'no punch in any of these').