Typical 28-Word Portion Of Memory Stack - Xerox 560 Reference Manual

PSS Operations PLS Operations
initial TSA - - terminal TSA
=
initial TSA-28
+1 (RO) -27
+2 (R 1) -26
+3 (R2) -25
+4 (R3) -24
+5
(R4)
-23
+6
(R5) -22
+7 (R6) -21
+8 (R7) -20
+9 (R8) -19
+10 (R9) -18
+11
(R10) -17
+12 (Rl1 ) -16
+13 (R12)
-15
+14 (R13) -14
+15
(R14)
-13
+16 (R15) -12
+17
-11
+18
-10
+19 -9
+20 -8
+21 -7
+22 -6
+23 -5
+24
-4
+25
(PSWl)
-3
+26 (PSW2)
-2
+27 (PSW3)
t -1
initial TSA +28 (PSW4)
- initial TSA
tAs a function of the hardware, the contents of these 8 locations are in-
determinate after a PSS instruction and ignored by a PLS instruction. These
locations are reserved for future enhancements and must not be used.
Figure 12. Typical 28-Word Portion of Memory Stack for PSS and PLS
102 Push-90wn Instructions (Privileged)