On: raising the semantic level of a program

[Rich Alderson]

From: Chuck Guzis 
Sent: Sunday, June 28, 2020 4:51 PM

> It's noteworthy that on the Univac 1100 series, a "byte" could be 6, 9
> or 12 bits, but not 8. (36 bit words).  The PDP-10 had similar issues,
> such as the "packed" string format of 5 7-bit characters per word, with
> one bit unused.

Of course, on the PDP-10, bytes can be anywhere from 1 to 36 bits long;
the size is defined in the pointer, not the hardware.

And in the 7-bit ASCII text format, bit 35 (the word is big-endian) *is*
used by the default editor:  In order to allow line numbering in source
files for languages which do not allow it, the line numbers are ASCII
strings with bit 35 set, and the monitor (=kernel=operating system) strips
them out before handing them to compilers' input streams.

                                                                Rich


Rich Alderson
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