feat(memtest): tidied memtest

src/memtest.s

@@ -9,15 +9,18 @@
 ;;
 ;; Memory Testing Routines
 ;;
+;; This family of BIOS routines does not return, upon completion the CHIBI must
+;; be reset.
+;;
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 
   SECTION MEMTEST
 
-  EXPORT RAMTEST
+  EXPORT ROBIT
 
 ; RAM testing routine. Ported to 6809 from 6800, based on source for ROBIT-2 for
 ; MIKBUG.
-RAMTEST
+ROBIT
   ldx #STACK_TOP+1     ; bottom of testable SRAM, $0200
 AGAIN@                 ; Store 1 in memory
   lda #1               ; Set [X] to 1
@@ -41,4 +44,17 @@ ERR@                   ; Write out error indicator
 PASS@                  ; Pass test
   ldb #'P
   jsr POUTCHAR
-  rts
+  bra HALT
+
+; Prints a message about completing a memory test prompting the user to reset
+; then puts the MPU in a loop where it only responds to interrupts, effectively
+; halting the CHIBI
+HALT
+  PZSTR MSG_FINISH
+LOOP@
+  sync
+  bra LOOP@
+
+MSG_FINISH
+  fcc "Memory test finished! Please reset"
+  fcb $0D,$0A,$00