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authorDuncan Smith2010-09-13 22:26:14 -0700
committerDuncan Smith2010-09-13 22:26:14 -0700
commit9b2d156b85a3c3eadbc8c4ab4726fcb6ec44e5d0 (patch)
treed816adf98456610fccf9c3c010937aa9151f3074
parent066cbff4c7666437575569edc61631060929c158 (diff)
Documentation update
-rw-r--r--README.markdown4
-rw-r--r--opcodes.asm3
2 files changed, 6 insertions, 1 deletions
diff --git a/README.markdown b/README.markdown
index 7750ab3..95ec567 100644
--- a/README.markdown
+++ b/README.markdown
@@ -42,6 +42,10 @@ instruction with a fixed 42 cycle overhead:
jmp 0(a3,d0) ;14 cycles
;; overhead: 42 cycles
+(Using techniques borrowed from
+[Tezxas](http://tezxas.ticalc.org/technica.htm) I will be able to get
+this to 30 cycles.)
+
From there, an instruction will take anywhere from 0 to, well, lots of
additional cycles. Generally, however, it will take under 50, for 92
total. In the worst reasonable case, a 4 cycle instruction emulated
diff --git a/opcodes.asm b/opcodes.asm
index 3239dd4..329a825 100644
--- a/opcodes.asm
+++ b/opcodes.asm
@@ -186,7 +186,7 @@ DONE MACRO
ENDM
;; Timing correction for more precise emulation
- ;;
+ ;;
;; \1 is number of tstates the current instruction should take
;; \2 is number of cycles taken already
TIME MACRO
@@ -673,6 +673,7 @@ emu_op_36:
emu_op_37:
;; SCF
;; Set Carry Flag
+ ;; XXX flags are more complicated than this :(
move.b #%00111011,flag_valid-flag_storage(a3)
move.b eaf,d1
ori.b #%00000001,d1