Proper fix for #235.

auxmem.shr.s

@@ -559,12 +559,7 @@ SHRRSCR1LINE
 
 
 * Clear from current location to EOL
-* TODO: I added a check on entry to bail out if not a GS in order to 
-*       fix #235. But I am not sure why this code is ever called in HGR mode.
-SHRCLREOL     BIT   VDUBANK                ; Check it is a GS ..
-              BMI   :GS                    ; .. easier to check here
-              RTS
-:GS           JSR   SHRCHARADDR
+SHRCLREOL     JSR   SHRCHARADDR
               STZ   VDUADDR+0              ; Addr of start of line
               LDA   #$08                   ; Eight rows of pixels
               STA   :CTR

auxmem.vdu.s

@@ -628,6 +628,7 @@ VDU12         STZ   FXLINES
               BIT   VDUSCREEN
               BPL   :NOTHGR
               JSR   HGRCLREOL
+              BRA   :NOTSHR
 :NOTHGR       BVC   :NOTSHR
               JSR   SHRCLREOL
 :NOTSHR       LDA   VDUTEXTY               ; ROW
@@ -727,6 +728,7 @@ SCROLLER      LDA   TXTWINTOP
               BIT   VDUSCREEN
               BPL   :NOTHGR
               JSR   HGRSCR1LINE            ; Scroll HGR screen
+              BRA   :NOTSHR
 :NOTHGR       BVC   :NOTSHR
               JSR   SHRSCR1LINE            ; Scroll SHR screen
 :NOTSHR       PLA
@@ -750,6 +752,7 @@ RSCROLLER     DEC   TXTWINTOP
               BIT   VDUSCREEN
               BPL   :NOTHGR
               JSR   HGRRSCR1LINE           ; Reverse scroll HGR screen
+              BRA   :NOTSHR
 :NOTHGR       BVC   :NOTSHR
               JSR   SHRRSCR1LINE           ; Reverse scroll SHR screen
 :NOTSHR       PLA