Discussion:
DEC Alpha?
(too old to reply)
Gareth Evans
2020-06-06 19:55:48 UTC
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Am I right in thinking that the instruction set only
offered 32 bit and 64 bit operations?

(Continued discussion from comp.sys.raspberry-pi)
r***@gmail.com
2020-06-06 21:51:36 UTC
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Post by Gareth Evans
Am I right in thinking that the instruction set only
offered 32 bit and 64 bit operations?
(Continued discussion from comp.sys.raspberry-pi)
Pretty much. There were insert and zap operations that could be used
to extract an insert bytes. And they added byte and word loads and stores
in a later revision; originally, Alpha could only load and store longwords
and quadwords.

The first round of workstations had "swizzle space" to do byte and word
I/O; some of the address bits were used to indicate which bytes were
involved in the transfer. This was truly annoying.
--
roger ivie
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Gareth Evans
2020-06-07 20:49:08 UTC
Permalink
Post by r***@gmail.com
Post by Gareth Evans
Am I right in thinking that the instruction set only
offered 32 bit and 64 bit operations?
(Continued discussion from comp.sys.raspberry-pi)
Pretty much. There were insert and zap operations that could be used
to extract an insert bytes. And they added byte and word loads and stores
in a later revision; originally, Alpha could only load and store longwords
and quadwords.
The first round of workstations had "swizzle space" to do byte and word
I/O; some of the address bits were used to indicate which bytes were
involved in the transfer. This was truly annoying.
Thanks. After 45 years in the industry I bethought me to be au
fait with most terms, but I'd not heard of Swizzle Space.

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