How much RAM is 64K 36bit words of Core Memory 794

On the PDP-10, the choices were:

1-bit bytes = 36 bytes per word. 2-bit bytes = 18 bytes per word. 3-bit bytes = 12 bytes per word. 4-bit bytes = 9 bytes per word. 5-bit bytes = 7 bytes per word with 1 bit left over. Error messages in the FORTRAN run-time system (FOROTS) were stored in 5-bit mode. Like BAUDOT, it had shift codes in order to handle a repertoire of more than 32 characters. 6-bit bytes = 6 bytes per word = SIXBIT. COBOL databases typically used SIXBIT. The Monitor Commands table was in SIXBIT. Directory entries (6 chars file name plus 3 chars extension) were SIXBIT. 7-bit bytes = 5 bytes per word with 1 bit left over. Plain ASCII text was 7-bit bytes, the end-of-line and-or end-of-block was padded with nulls, EOL = CR+LF. 8-bit bytes = 4 bytes per word with 4 unused bits. Used for reading magtapes written on PDP-11 or IBM-360. 9-bit bytes = 4 bytes per word (not used very often). 12-bit bytes = 3 bytes per word. 16-bit bytes = 2 bytes per word with 4 unused bits (also PDP-11). 18-bit bytes = 2 bytes per word. 36-bit bytes = 1 byte per word.

The PDP-10 byte load and byte deposit instructions were size agnostic. It could handle any number of bits per byte with equal ease.

-Joe