pdp11_sequencer: BUGFIX: use I space for all mode=1,2,3 if reg=pc

- tcode/cpu_mmu.mac: add test F1.1 (verify fix)

Closes #35

doc/CHANGELOG.md

@@ -95,6 +95,8 @@ The full set of tests is only run for tagged releases.
   - rtl/w11a
     - pdp11_mmu: BUGFIX: correct trap and PDR A logic, see
         [ECO-033](ECO-033-MMU_AFC-1_PDR-A.md)
+    - pdp11_sequencer: BUGFIX: use I space for all mode=1,2,3 if reg=pc, see
+        [ECO-034](ECO-034-MMU_d-space-pc.md)
   - src/librwxxtpp
     - RtclRw11Cpu.cpp: quit before mem write if asm-11 error seen
   - tools/asm-11/lib

doc/ECO-034-MMU_d-space-pc.md

@@ -0,0 +1,53 @@
+# ECO-033: D space used instead of I space for some PC specifiers  (2022-09-08)
+
+### Scope
+- was in w11a since 2009
+- affects: all w11a systems
+
+### Symptom summary
+Test 072 of `ekbee1` fails with
+```
+    D-SPACE ENABLE CIRCUITRY HAS FAILED
+    ERROR   AUTOI/D VIRTUAL
+    REGISTR REGISTR ADDRESS TESTNO  PC AT ABORT
+    100027  000000  060410  000072  060412  
+    100027  000027  060416  000072  060422  
+```
+The test does
+```
+    060410: tst  (pc)
+    060416: cmp  #240,(pc)
+```
+and expects that these accesses are done to I space.  
+They are done to D space instead.
+
+### Analysis
+The w11 used D space only for `(pc)+` and `@(pc)+` specifiers.    
+The w11a has 4 specifier flows
+- srcr: for source read
+- dstr: for destination read (in `CMP`, `BIT`, `TST`, ...)
+- dstw: for destination write (also read-modify-write)
+- dsta: for destination address (in `JSR`, `JMP`)
+A code review showed what was OK and what needed a fix
+```
+s_srcr_def      OK                 mov (pc),r0
+s_srcr_inc      OK                 mov #123,r0
+s_dstr_def      FIXED              cmp,#123,(pc)
+s_dstr_inc      OK                 cmp r0,#123
+s_dstw_def      FIXED              mov r0,(pc)    modifies I space code !
+s_dstw_inc      FIXED for mode=2   mov r0,#133    modifies I space code !
+s_dstw_inc      OK    for mode=3   mov r0,@#lbl
+s_dsta_inc      OK                 
+```
+
+Note: the 11/70 uses D space for modes 1-5 in the source specifier flow,
+and for mode 1-3 in the destination specifier flow.
+
+### Fixes
+Add `pispace` modifiers for the `do_memread*` and `do_memwrite*` calls in
+pdp11_sequencer.vhd.
+
+### Hindsight
+Took 13 years to fix. The fixed address modes are of very little practical
+value and are not used in normal code. And certainly used not when running
+with kernel D mode enabled.

doc/README_known_issues.md

@@ -3,29 +3,6 @@ Notes
 - resolved issues are summarized in [resolved issues](README_resolved_issues.md)
 - the case id indicates the release when the issue was first recognized.
 
-### V0.791-3 {[issue #35](https://github.com/wfjm/w11/issues/35)} -- MMU: D space used instead of I space for PC deferred specifiers
-
-Test 072 of `ekbee1` fails with
-```
-    D-SPACE ENABLE CIRCUITRY HAS FAILED
-    ERROR   AUTOI/D VIRTUAL
-    REGISTR REGISTR ADDRESS TESTNO  PC AT ABORT
-    100027  000000  060410  000072  060412
-    100027  000027  060416  000072  060422
-```
-The test does
-```
-    060410: tst  (pc)
-    060416: cmp  #240,(pc)
-```
-and expects that these accesses are done to I space.  
-They are done to D space instead.
-
-The w11 uses D space only for `(pc)+` and `@(pc)+` specifiers.  
-Clearly a bug.  
-Wasn't detected so far because this access mode has no practical value  
-and this therefore not used in normal software.
-
 ### V0.50-2 {[issue #28](https://github.com/wfjm/w11/issues/28)} -- RK11: write protect action too slow
 
 Some simple RK11 drivers, especially in test codes, don't poll for completion