CR11 Controller

From Computer History Wiki
(Redirected from CR11)
Jump to: navigation, search
M8291 version

The CR11 Controller was a UNIBUS device controller for the CR11 Card Readers. It could also be used with the GDI 100M Optical Mark Reader, which read 12-row 40-column marked cards; in such use, the complete sub-system was called the CM11 Card Reader System.

The CR11 used programmed I/O.

The original version was the M829, a dual format card, which was mounted in an SPC slot; it was used with an M105 Address Selector and an M782 Interrupt Control (both tall singles).

M8290 version

Later versions were the M8290 and M8291 quad format cards, also mounted in an SPC slot. The difference between the two is not yet known. All the card versions are program compatible.

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').