Introduce label IOStatus and unify i/o-status? code word across cbm versions

6502/C64/src/vf-sys-c16.fth

@@ -7,6 +7,7 @@ include vf-lbls-cbm.fth
 \ C16-Labels                 clv13.4.87)
 
 0ff4c >label ConOut
+  090 >label IOStatus
   09a >label MsgFlg
   099 >label OutDev
   098 >label  InDev
@@ -55,8 +56,6 @@ end-code
 
 include vf-sys-cbm.fth
 
-: i/o-status?  $90 c@ ;
-
 
 \ *** Block No. 143, Hexblock 8f
 \ ... continued

6502/C64/src/vf-sys-c64.fth

@@ -7,6 +7,7 @@ include vf-lbls-cbm.fth
 \ C64-Labels                 clv13.4.87)
 
 0E716 >label ConOut
+  090 >label IOStatus
   09d >label MsgFlg
   09a >label OutDev
   099 >label  InDev
@@ -58,8 +59,6 @@ Code curoff   ( --)
 
 include vf-sys-cbm.fth
 
-: i/o-status?  $90 c@ ;
-
 
 \ *** Block No. 143, Hexblock 8f
 \ ... continued

6502/C64/src/vf-sys-cbm.fth

@@ -99,6 +99,9 @@ Output: display   [ here output ! ]
 \ *** Block No. 135, Hexblock 87
 87 fthpage
 
+Code i/o-status?  ( -- n )
+  IOStatus lda  Push0A jmp  end-code
+
 \ b/blk drive >drive drvinit  clv14:2x87
 
 400 Constant b/blk
@@ -143,10 +146,10 @@ Label nodevice     0 # ldx  1 # ldy
 \ ?device                     clv12jul87
 
 Label (?dev
- 90 stx (C16 $ae sta ( ) LISTEN jsr
+ IOStatus stx (C16 $ae sta ( ) LISTEN jsr
         \ because of error in OS
  60 # lda  SECOND jsr  UNLSN jsr
- 90 lda  0<> ?[ pla pla nodevice jmp ]?
+ IOStatus lda  0<> ?[ pla pla nodevice jmp ]?
  rts    end-code
 
  Code (?device  ( dev --)

6502/C64/src/vf-sys-x16.fth

@@ -6,6 +6,7 @@ include vf-lbls-cbm.fth
 \ X16 labels
 
 0c28c >label ConOut
+ 0286 >label IOStatus
  028c >label MsgFlg
  028b >label OutDev
  028a >label  InDev
@@ -75,8 +76,6 @@ Code curoff   ( --)
 
 include vf-sys-cbm.fth
 
-: i/o-status?  $0286 c@ ;
-
 
 \ *** Block No. 143, Hexblock 8f
 \ ... continued