HLT - Revision history

Mr z: Protected "HLT" ([edit=autoconfirmed] (indefinite) [move=autoconfirmed] (indefinite))

2010-12-04T08:27:41Z

Protected "HLT" ([edit=autoconfirmed] (indefinite) [move=autoconfirmed] (indefinite))

2005-01-24T18:28:55Z

2005-01-24T18:28:04Z

2005-01-24T01:49:11Z

2005-01-17T17:06:01Z

2005-01-11T21:51:34Z

2005-01-11T21:16:20Z

2005-01-11T21:14:55Z

2005-01-11T21:14:36Z

2005-01-11T21:14:08Z

@@ Line 10: / Line 10: @@
 <tr><td>Addressing Mode</td><td>[[Implied Mode|Implied]]</td></tr>
 </table><br/>
-The Halt (HLT) instruction halts the [[CP1610]].  The CPU asserts its HALT output, and performs no further processing once it executes this instruction.  The CPU ignores interrupts as well until the CPU gets reset.  HLT is mainly useful for debugging.<br/><br/>
+The Halt (HLT) instruction halts the [[CP1610]].  The CPU asserts its HALT output, and performs no further processing once it executes this instruction.  The CPU ignores interrupts as well until the CPU is reset, or unhalted by a negative pulse on STPST.  HLT is mainly useful for debugging.<br/><br/>
 A pulse on the STPST input will restart a halted CPU.  On the Intellivision, this is mostly irrelevant as STPST tied to a fixed value.  The CPU is socketed, however, so one could modify their Intellivision in order to make this useful, say with a "debugging support" daughtercard.

@@ Line 11: / Line 11: @@
 </table><br/>
 The Halt (HLT) instruction halts the [[CP1610]].  The CPU asserts its HALT output, and performs no further processing once it executes this instruction.  The CPU ignores interrupts as well until the CPU gets reset.  HLT is mainly useful for debugging.<br/><br/>
-A pulse on the STPST input will restart a halted CPU.  On the Intellivision, this is mostly irrelevant as STPST tied to a fixed value.  The CPU is socketed, however, so one could modify their Intellivision in order to make this useful.
+A pulse on the STPST input will restart a halted CPU.  On the Intellivision, this is mostly irrelevant as STPST tied to a fixed value.  The CPU is socketed, however, so one could modify their Intellivision in order to make this useful, say with a "debugging support" daughtercard.

@@ Line 10: / Line 10: @@
 <tr><td>Addressing Mode</td><td>[[Implied Mode|Implied]]</td></tr>
 </table><br/>
-The Halt (HLT) instruction halts the [[CP1610]].  The CPU performs no further processing after receiving this instruction.  This also means that all further masked interrupts are ignored as well until the CPU gets reset.<br/><br/>
+The Halt (HLT) instruction halts the [[CP1610]].  The CPU asserts its HALT output, and performs no further processing once it executes this instruction.  The CPU ignores interrupts as well until the CPU gets reset.  HLT is mainly useful for debugging.<br/><br/>
-Currently, it is unknown whether an unmasked interrupt arriving on the INTR input, or if a pulse on the STPST input will restart a halted CPU.  The existing CP1610 documentation does not say.  On the Intellivision, this is irrelevant as both inputs are tied to fixed values.  HLT is mainly useful for debugging.
+A pulse on the STPST input will restart a halted CPU.  On the Intellivision, this is mostly irrelevant as STPST tied to a fixed value.  The CPU is socketed, however, so one could modify their Intellivision in order to make this useful.

@@ Line 6: / Line 6: @@
 <tr><td>Interruptible</td><td>No</td></tr>
 <tr><td>Opcode Range</td><td>$0000</td></tr>
 </table><br/>
 The Halt (HLT) instruction halts the [[CP1610]].  The CPU performs no further processing after receiving this instruction.  This also means that all further masked interrupts are ignored as well until the CPU gets reset.<br/><br/>
 Currently, it is unknown whether an unmasked interrupt arriving on the INTR input, or if a pulse on the STPST input will restart a halted CPU.  The existing CP1610 documentation does not say.  On the Intellivision, this is irrelevant as both inputs are tied to fixed values.  HLT is mainly useful for debugging.

@@ Line 7: / Line 7: @@
 <tr><td>Opcode Range</td><td>$0000</td></tr>
 </table><br/>
-The Halt (HLT) instruction halts the cpu.  The cpu performs no further processing after receiving this instruction.  This also means that all further interrupts are ignored as well.<br/><br/>
+The Halt (HLT) instruction halts the [[CP1610]].  The CPU performs no further processing after receiving this instruction.  This also means that all further masked interrupts are ignored as well until the CPU gets reset.<br/><br/>

← Older revision	Revision as of 08:27, 4 December 2010
(No difference)

@@ Line 1: / Line 1: @@
 [[Category:CP1610]]
 <table border>
 <tr><td>Instruction Name</td><td>Halt</td></tr>
@@ Line 8: / Line 6: @@
 <tr><td>Interruptible</td><td>No</td></tr>
 <tr><td>Opcode Range</td><td>$0000</td></tr>
-</table>
+</table><br/>