Assembly Syntax Overview - Revision history

Mr z: Protected "Assembly Syntax Overview" ([edit=autoconfirmed] (indefinite) [move=autoconfirmed] (indefinite))

2010-12-04T07:53:49Z

Protected "Assembly Syntax Overview" ([edit=autoconfirmed] (indefinite) [move=autoconfirmed] (indefinite))

2007-10-11T06:36:15Z

‎Using PROC / ENDP

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‎Operators

2007-10-11T06:34:13Z

‎Using PROC / ENDP

2007-10-10T18:15:40Z

‎Forward References

2007-10-10T17:49:05Z

‎Precision

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‎Operand Order

2007-10-10T17:43:55Z

‎Common Directives =

2007-10-10T17:38:20Z

‎Operand Order

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‎Operand Order

@@ Line 62: / Line 62: @@
 Example:
 <CODE>
-    ;; Loop 42 times and return
+ ;; Loop 42 times and return
-    FOO     PROC
+ FOO     PROC
-            MVII    #42,  R0
+         MVII    #42,  R0
-    <B>@@loop:</B> DECR    R0
+ <B>@@loop:</B> DECR    R0
-            BNEQ    @@loop
+         BNEQ    @@loop
-−
-            JR      R5
+         JR      R5
-            ENDP
+         ENDP
-−
-    ;; Loop 57 times and return
+ ;; Loop 57 times and return
-    BAR     PROC
+ BAR     PROC
-            MVII    #57,  R0
+         MVII    #57,  R0
-            B       <B>FOO.loop</B>   ; Reuse FOO's loop.
+         B       <B>FOO.loop</B>   ; Reuse FOO's loop.
-            ENDP
+         ENDP
+ </CODE>
 In this example, the branch in FOO refers the local label "@@loop" by its local name.  The branch in BAR refers to the same label by its global name, "FOO.loop".

@@ Line 140: / Line 140: @@
 <TR><TH COLSPAN=2>DEFINED</TH><TD>Returns 1 if symbol is defined at this point (first pass)</TD></TR>
 </TABLE>
 == Forward References ==

@@ Line 61: / Line 61: @@
 Example:
-<CODE><pre>
+<CODE>
-;; Loop 42 times and return
+    ;; Loop 42 times and return
-FOO     PROC
+    FOO     PROC
-        MVII    #42,  R0
+</CODE>
 In this example, the branch in FOO refers the local label "@@loop" by its local name.  The branch in BAR refers to the same label by its global name, "FOO.loop".

@@ Line 172: / Line 172: @@
 </pre></CODE>
-Also, the assembler will issue a warning if you have a forward reference to an EQU or SET directive.  It's usually safe to ignore the warnings for EQU directives, but not for SET directives if the label's value gets SET more than once.  The following example triggers warnings:
+Also, the assembler will issue a warning if you have a forward reference to an EQU or SET directive.  It's usually safe to ignore the warnings for EQU directives, but not for SET directives if the label's value gets SET more than once.  The following examples trigger warnings:
 <CODE><pre>

@@ Line 198: / Line 198: @@
 == Precision ==
-Expressions are computed with 32-bit precision.  This makes it easy to do extended precision work.  If you try to use a 32-bit value as an operand to an instruction or one of the data directives (e.g. DECLE), though, the assembler will complain that the value is out of range.  The assembler allows values in the range $FFFF8000 (-32768) to $0000FFFF (+65535).
+Expressions are computed with 32-bit precision.  This makes it easy to do extended precision work.  If you try to use a 32-bit value as an operand to an instruction or one of the data directives (e.g. DECLE), though, the assembler will complain that the value is out of range.  The assembler allows 32-bit values in the range $FFFF8000 (-32768) to $0000FFFF (+65535) to silently truncate to 16 bits&mdash;that is, they will truncate without an error.
 Examples:
@@ Line 211: / Line 211: @@
          MVII    #MAGIC AND $FFFF, R0 ; Valid
          MVII    #MAGIC SHR 16, R0    ; Also valid
 </pre></CODE>
 = Example =

← Older revision	Revision as of 07:53, 4 December 2010
(No difference)

@@ Line 29: / Line 29: @@
 The next field is the instruction/directive field.  Instructions and directives are always preceded by at least one white-space character, or a label with a colon.  The [[CP1610]] page lists all of the instructions.
-== Operand Order ==
+=== Operand Order ===
 Many instructions have two operands.  In CP1610 assembly code, the last operand is generally the "destination" of the result, and the operands before it are "sources."  For example:

@@ Line 39: / Line 39: @@
      [[JSR]] R5, foo  ; Jump to "foo", and put return address in "R5."
-== Common Directives ===
+=== Common Directives ===
 * <CODE>ROMW</CODE>:  Sets the current "ROM width."  In most cases, you can use "ROMW 16", which is also the default.  Set this once per program.

@@ Line 35: / Line 35: @@
      [[ADDR]] R0, R1  ; Compute "R0 + R1" and put the result in "R1".
-Some instructions, like [[JSR]] don't quite fit that model:
+A couple instructions, like [[JSR]] don't quite fit that model:
      [[JSR]] R5, foo  ; Jump to "foo", and put return address in "R5."