error on echo.asm

vaja2/vhod_izhod/echo.asm

@@ -0,0 +1,81 @@
+ECHO START 0
+    LDA #97
+    STA number
+    JSUB char
+    JSUB nl
+    JSUB char 
+    JSUB nl    
+    +LDA #test_niz
+    JSUB string
+    JSUB nl
+    LDA number
+    JSUB num
+HALT J HALT
+    END ECHO
+
+.izpis znaka
+char WD #1
+     RSUB
+
+.izpis newline
+nl  +STA old_A
+    CLEAR A
+
+    LDCH newline
+    WD #1
+    
+    +LDA old_A
+    RSUB
+
+.izpis niza
+string   +STA strptr
+loop_niz CLEAR A
+         LDCH @strptr
+         WD #1
+         COMP #0
+         JEQ out
+         +LDA strptr
+         ADD #1
+         +STA strptr 
+         J loop_niz 
+out  RSUB
+    
+.desetiski izpis stevila v A iz HEX
+->ERRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRROR
+num     LDX digits_ix
+        STA number
+        DIV #10
+        STA quot
+        MUL #10
+        STA subtrahend
+        LDA number
+        SUB subtrahend
+        STCH digits, X
+        LDA digits_ix
+        ADD #1
+        STA digits_ix
+        LDA number
+        DIV #10
+        COMP #0
+        JGT num
+    .izpis v tabele v obratnem vrstnem redu
+loop_num  LDX digits_ix
+          LDA digits, X
+          JSUB char
+          LDA digits_ix
+          SUB #1
+          STA digits_ix
+          COMP #-1
+          JGT loop_num
+          RSUB 
+
+old_A WORD 0 
+newline BYTE 10
+test_niz BYTE C'hello world'
+         BYTE 0
+strptr WORD 0
+quot WORD 0
+subtrahend WORD 0
+number WORD 0 
+digits RESB 100
+digits_ix WORD 0