105 FOOBAR ?

[ams]

Hi and sorry for asking here, it is "sorta" (by a long stretch!) related to Lisp Machine keyboards though (in that it is part of the magic "RIGHT-CTRL RIGHT-META CALL" sequence) ... @MMcM Do you know where from "105 FOOBAR" might come from, like why is it called that ... and what is 109FOO, why 109 ...

On the CADR, in the console debugger (CC); there is a command called "105 FOOBAR" that starts the machine. Some random documentation documents it as follows:

LISP-TOP-LEVEL1			[QEV]
				Called by LISP-TOP-LEVEL, makes a few
				tests ("diagnostic self-test on
				power-on") then says 105 FOOBAR and
				enters a read-eval-print loop. 

Procedure to load a new Cold Load:    (as of 4/14/78) 

1)   Load COLD-LOAD itself by typing (LOAD-COLD) to the Lisp level of CC.
2)   Start the load and verify that it basically runs.  The first time you
     start it, it will take about 15 seconds before it says 105 foobar.
3)   Load a FILE job on PDP-10.
4)   Type (QLD) on the Lisp Machine, and answer "Yes" to all questions.
     Expect it to take 11 minutes.  Don't be surprised that QFASL gets
     loaded twice, also currently LISP-TOP-LEVEL, ERROR, SPECIAL, & UNSPECIAL.
5)   When it halts, (CC-DISK-SAVE <N>). Label as "With World".

.SBTTL 105 FOOBAR ROUTINE

;IF THE MACHINE IS STOPPED, AND SOMEONE HITS RIGHT-CTRL RIGHT-META CALL
;ON THE KNIGHT KEYBOARD, RESTART THE MACHINE.  SAVES WALKING TO THE OTHER ROOM.
FOO105:	TST CTRUN
	BMI FOO109		;JUMP IF RUNNING
	BIT #20000,164002	;ALSO TEST IF MACHINE REALLY RUNNING
	BNE FOO109		; (THIS EXPECIALLY FOR PDP-10 MODE)
	TST 164102
	BPL FOO109		;JUMP IF KEYBOARD NOT READY
	MOV 164100,-(SP)	;GET INPUT, CLEAR KEYBOARD (OK SINCE MACH STOPPED)
	COM (SP)		;COMPENSATE FOR BRAIN BUBBLES
	BIC #165700,(SP)	;CLEAR ALL BUT RIGHT CTL, RIGHT META, KEYCODE
	CMP (SP)+,#12020	;CHECK FOR CONTROL META CALL
	BNE FOO109
	MOV #1,CNUM		;1@G
	JSR PC,QG
	JSR PC,QDPGO		;^P
FOO109:	RTS PC