Difference between revisions of "CD11 High-Speed Punched Card Reader Control Unit"

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The CD11 High-Speed Punched Card Reader Control Unit was a UNIBUS device controller for the CR04 punched card reader. It used DMA to transfer data.

Registers

The controller has four control and buffer registers, which can be configured to any four sequential word locations in the I/O page; it is normally configured to addresses 772460-774666:

Register Abbreviation Address
Status and Control Register CDST 772460
Column Count Register CDCC 772462
Current Address Register CDBA 772464
Data Buffer Register CDDB 772466

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 and Control Register (CDST)

ERR HDR CHK EOF OFFLINE DATA ERR DATA LT NXM PWR CLR RDY INT ENB EXT BUS ADDR RDR ONLINE HOPPER CHECK DATA PACK READ
15 14 13 12 11 10 09 08 07 06 05 04 03 02 01 00

Column Count Register (CDCC)

CC15 <---> CC00
15 14 13 12 11 10 09 08 07 06 05 04 03 02 01 00

Current Address Register (CDBA)

BA15 <---> BA00
15 14 13 12 11 10 09 08 07 06 05 04 03 02 01 00

Data Buffer Register (CDDB)

The format of the contents this register depends on the setting of the 'Data Packing' bit in the CSR. If 0, '12-bit word', it holds 12-bit raw data from the card:

Unused Zones 12-11 Zones 0-9
15 14 13 12 11 10 09 08 07 06 05 04 03 02 01 00

If 1, '8-bit byte', it holds 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'):

Unused Zone 12 Zone 11 Zone 0 Zone 9 Zone 8 Code Zones 1-7
15 14 13 12 11 10 09 08 07 06 05 04 03 02 01 00

Implementation

It was constructed from a number of smaller FLIP CHIPs which were installed in custom 4-slot system unit backplane. The modules are:

  • M112 - 10 x 2-input NOR gates
  • 2 x M113 - 10 x 2-input NAND gates
  • M117 - 6 x 4-input NAND gates
  • M203 - 8 x 'S-R' flip-flops
  • M205 - 5 x 'D' flip-flops
  • M239 - 3 x 4-bit counter/register
  • M304 - One-shot delay
  • M611 - High speed power inverters
  • M721 - Bus interface
  • M7249 - Hollerith check
  • M783 - Bus drivers
  • M784 - Bus receivers
  • M796 - UNIBUS Master Control
  • M7821 - Interrupt Control
  • M957 - Ribbon cable connector
  • M7219 - Bus Interface

The M7219 is a quad card; the others are all single. (Of those, the M783, M784, M796, M7821 and M957 are extended length; most of the others are all standard length.)

Board locations (as seen from the board insertion side of the backplane, not the wire-wrap pin side, as is common in DEC documentation) are:

Connector
Slot A B C D E F
1 UNIBUS In M7219
2 M721 M957 M784 M783 M7821 M796
3 M113 M239 M7249 M611 M117 M205
4 UNIBUS Out M113 M112 M304 M203

External links

Retrieved from "https://gunkies.org/w/index.php?title=CD11_High-Speed_Punched_Card_Reader_Control_Unit&oldid=28049"