Difference between revisions of "KE11-B Extended Arithmetic Element"

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** arithmetic shift
 
** arithmetic shift
 
** [[normalization]]
 
** [[normalization]]
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(The last is used for implementation of [[floating point]] in [[software]].)
  
 
The original KE11-A was produced for use with the [[PDP-11/20]], whose [[KA11 CPU]] did not have multply, divide, or multi-bit shift operations. As a UNIBUS peripheral, not integrated into the [[Central Processing Unit|CPU]], it was also usable with other models, e.g. the [[PDP-11/05]] and [[PDP-11/04]], which likewise did not implement multiplication in [[hardware]], etc. The KE11-B can be used with these later models.
 
The original KE11-A was produced for use with the [[PDP-11/20]], whose [[KA11 CPU]] did not have multply, divide, or multi-bit shift operations. As a UNIBUS peripheral, not integrated into the [[Central Processing Unit|CPU]], it was also usable with other models, e.g. the [[PDP-11/05]] and [[PDP-11/04]], which likewise did not implement multiplication in [[hardware]], etc. The KE11-B can be used with these later models.

Revision as of 12:07, 7 January 2020

The KE11-B Extended Arithmetic Element is a program-compatible re-implementation (on a single hex board - the M7840) of the KE11-A Extended Arithmetic Element, an autonomous UNIBUS peripheral which can perform a variety of arithmetic or logical operations:

  • multiplication
  • division
  • multi-bit shifts

(The last is used for implementation of floating point in software.)

The original KE11-A was produced for use with the PDP-11/20, whose KA11 CPU did not have multply, divide, or multi-bit shift operations. As a UNIBUS peripheral, not integrated into the CPU, it was also usable with other models, e.g. the PDP-11/05 and PDP-11/04, which likewise did not implement multiplication in hardware, etc. The KE11-B can be used with these later models.