> On Jan 7, 2019, at 12:24 AM, Dave Wade via cctalk <cctalk@classiccmp.org> 
> wrote:
> 
> ...
> I am also pretty sure that prior to S/360 the term "character" was generally 
> used for non 8-bit character machines. I am not familiar with the IBM 70xx 
> series machines but certainly on the 1401 and 1620 the term byte was never 
> used.

The 1620 is a decimal machine, with digit-addressed memory.  It has a number of 
instructions that operate on digit pairs, for I/O, so those pairs are called 
"characters".

> Also the Honeywell H3200 which was an IBM1401 "clone" (sort of). The only 
> machine I know where a "byte" is not eight bits is the Honeywell L6000 and 
> its siblings These machines had 36 bit works which were originally divided 
> into 6 six bit characters. 

Others have already pointed out there are plenty of other examples, with other 
definitions.  I mentioned the CDC 6000 series mainframes.

Just to make sure of my memory, I searched some documentation.  Here is a quote 
from the CDC Cyber 170 series Hardware Reference Manual (section "Input/output 
multiplexor - Model 176"):

"During communications between the PPUs and CM, the I/O MUX disassembles 60-bit 
transmissions from CM to 12-bit bytes."

But here's one I had not seen before: in the 7600 Preliminary System 
Description, the section that describes the PPU I/O machinery has the same sort 
of wording as above, but then on the next page the discussion of the drum 
memory says:

"A 16 bit cyclic parity byte is generated by the controller for the data field 
of each record written on the peripheral unit."

And the CDC 6000 series Sort-Merge utility has a "BYTESIZE" control card, which 
in PDP-10 fashion allows "byte" to be any length up to 60 bits (the word size) 
-- the default is 6 bits, which is character length for the basic character set 
but other examples show 12 and 60 bit "bytes".  In the same way, a TUTOR 
language manual from 1978 describes bytes as being any size, in a description 
of the language feature for what C calls bit-field variables.  I didn't realize 
that term was used for that feature, though.

        paul

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