Difference between revisions of "HLT"
| Line 6: | Line 6: | ||
<tr><td>Interruptible</td><td>No</td></tr> | <tr><td>Interruptible</td><td>No</td></tr> | ||
<tr><td>Opcode Range</td><td>$0000</td></tr> | <tr><td>Opcode Range</td><td>$0000</td></tr> | ||
| + | <tr><td>Input Flags</td><td>None</td></tr> | ||
| + | <tr><td>Output Flags</td><td>None</td></tr> | ||
| + | <tr><td>Addressing Mode</td><td>[[Implied Mode|Implied]]</td></tr> | ||
</table><br/> | </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 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. | 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. | ||
Revision as of 17:06, 17 January 2005
| Instruction Name | Halt |
| Mnemonic | HLT |
| CP1610 Clock Cycles | Infinity |
| Interruptible | No |
| Opcode Range | $0000 |
| Input Flags | None |
| Output Flags | None |
| Addressing Mode | Implied |
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.
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.
