usermem-z80-thunked: Fix offsets for 32K/32K mode

With this fixed we can attempt (and fail) to mount a file system

diff --git a/Kernel/usermem_std-z80-thunked.s b/Kernel/usermem_std-z80-thunked.s
index 9d10cc0..412c3e0 100644 (file)
--- a/Kernel/usermem_std-z80-thunked.s
+++ b/Kernel/usermem_std-z80-thunked.s
@@ -25,6 +25,7 @@
 
 
 ;      HL = user address, BC = length, DE = kaddr
+;      IX = page pointer
 ;
 ;      On return
 ;      Z       HL = address to write to, BC = length, DE = kaddr
@@ -55,7 +56,7 @@ user_mapping:
        ;
 one_high_map:
        res 7,h
-       ld a,2(ix)
+       ld a,1(ix)
        call map_page_low
        xor a
        ret
@@ -114,6 +115,8 @@ uputget:
         ; load DE with destination address (in userspace)
         ld e, 6(ix)
         ld d, 7(ix)
+       ; And now load ix with our paging pointer
+       ld ix,#U_DATA__U_PAGE
        ret
 
 __uget:
@@ -161,11 +164,17 @@ __uzero:
        ld a,b
        or c
        ret z
+       push ix
+       ld ix,#U_DATA__U_PAGE
        call user_mapping
-       jr z, zeroit
+       jr z, zeroit_1
        call zeroit
        exx
+zeroit_1:
        call user_mapping
+       call zeroit
+       pop ix
+       ret
 zeroit:
        ld (hl),#0
        dec bc
@@ -186,7 +195,7 @@ __ugetc:
        bit 7,(hl)
        ld a,(U_DATA__U_PAGE)
        jr z, ugetcl
-       ld a,(U_DATA__U_PAGE + 2)
+       ld a,(U_DATA__U_PAGE + 1)
 ugetcl:
        call map_page_low
        ld l,(hl)
@@ -201,7 +210,7 @@ __ugetw:
        push bc
        bit 7,(hl)
        jr z, ugetwl
-       ld a,(U_DATA__U_PAGE + 2)
+       ld a,(U_DATA__U_PAGE + 1)
        call map_page_low
        res 7,h
        ld a,(hl)
@@ -220,7 +229,7 @@ ugetwl:
        ld l,a
        ld a,(0)                ; Split can only mean one address
        ld h,a
-       ld a,(U_DATA__U_PAGE + 2)
+       ld a,(U_DATA__U_PAGE + 1)
        jp map_kernel_low
 
 __uputc:
@@ -233,7 +242,7 @@ __uputc:
        bit 7,(hl)
        ld a,(U_DATA__U_PAGE)
        jr z, uputcl
-       ld a,(U_DATA__U_PAGE + 2)
+       ld a,(U_DATA__U_PAGE + 1)
 uputcl:
        call map_page_low
        ld (hl),e
@@ -248,7 +257,7 @@ __uputw:
        push bc
        bit 7,(hl)
        jr z, uputwl
-       ld a,(U_DATA__U_PAGE + 2)
+       ld a,(U_DATA__U_PAGE + 1)
        call map_page_low
        res 7,h
        ld (hl),e
@@ -263,7 +272,7 @@ uputwl:
        inc hl
        bit 7,h
        jr z, normal_pwl
-       ld a,(U_DATA__U_PAGE + 2)
+       ld a,(U_DATA__U_PAGE + 1)
        ld a,d
        ld (0),a                ; Split can only mean one address
        jp map_kernel_low