cromemco: get the task switching logic working right

diff --git a/Kernel/platform-cromemco/tricks.s b/Kernel/platform-cromemco/tricks.s
index 065e35e..05b7987 100644 (file)
--- a/Kernel/platform-cromemco/tricks.s
+++ b/Kernel/platform-cromemco/tricks.s
@@ -135,19 +135,28 @@ not_swapped:
        push de
 
        ; Trick - we don't overlay the udata proper with anything so we can
-       ; map common and ldir
-       ld a,#0x81
-       out (0x40),a
-       ld hl, #U_DATA_STASH
-       ld de, #U_DATA
+       ; map common as write, process as read and ldir
+       ; Or we could expect it blows up the emulator so do it the slow way
+       ; for now
+;      or #0x80
+;      out (0x40),a
+;      ld hl, #U_DATA_STASH
+;      ld de, #U_DATA
+;      ld bc, #U_DATA__TOTALSIZE
+;      ldir
+;      ld a,#1         ; back to kernel
+;      out (0x40),a
+
+       ld hl,# U_DATA_STASH
+       ld ix, #U_DATA
        ld bc, #U_DATA__TOTALSIZE
-       ldir
-       ld a,#1         ; back to kernel
-       out (0x40),a
+       ld d,a
+       ld e,#0x01
+       call ldir_far
 
        pop de
 
-       ; In the non swap case we must set so before we use the stack
+       ; In the non swap case we must set sp before we use the stack
        ; otherwise we risk corrupting the restored stack frame
         ld sp, (U_DATA__U_SP)
 
@@ -260,7 +269,7 @@ _dofork:
        ; we must not touch the parent uarea after this point, any
        ; changes only affect the child
        ld hl, #U_DATA          ; copy the udata from common into the
-       ld de, #U_DATA_STASH    ; target process
+       ld ix, #U_DATA_STASH    ; target process
        ld bc, #U_DATA__TOTALSIZE
 
        call ldir_to_user
@@ -304,8 +313,8 @@ _need_resched:      .db 0
        ;       This one is really hard to do at a sensible speed
        ;
 bankfork:
-       ld d,c                  ; source
-       ld e,a                  ; dest
+       ld d,a                  ; source
+       ld e,c                  ; dest
        ld hl,#0x0000
        ld ix,#0x0000
        ld bc,#0xF000