---
title: "Halt Right There!"
type: "article"
slug: "halt-right-there"
url: "http://localhost/article/halt-right-there/"
markdown_url: "http://localhost/article/halt-right-there.md"
published_at: "2020-10-27T17:09:49+00:00"
modified_at: "2024-05-26T13:52:14+00:00"
featured_image:
  url: "http://localhost/wp-content/uploads/2022/04/20230809-041332.jpg"
excerpt: "You ZX/TS users have been told, and told again, \"Don't mess with the interrupts\" and \"Never use the HALT command.\" The severity of the admonitions seem to imply that a fate-worse-than-crashing awaits those who would tamper with such things. When HALT is encountered, the Z80 CPU stops running your program. In this way it is…"
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  - name: "Timex/Sinclair 1000"
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indiv:
  - name: "Fred Nachbaur"
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publication: "SyncWare News"
publication_r:
  id: 10245
  title: "SyncWare News"
  type: "periodical"
  url: "http://localhost/periodical/syncware-news/"
authors: "Fred Nachbaur"
volume: "3"
issue: "6"
issues_articles:
  - id: 26687
    title: "SyncWare News v3 n6"
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pages: "23-24"
pubdate: "Jul-Aug 1986"
archive_link: false
volumeissue: "v3n6"
---

# Halt Right There!

You ZX/TS users have been told, and told again, “Don’t mess with the interrupts” and “Never use the HALT command.” The severity of the admonitions seem to imply that a fate-worse-than-crashing awaits those who would tamper with such things. When HALT is encountered, the Z80 CPU stops running your program. In this way it is like the BASIC STOP command. More precisely, it endlessly executes NOPs (no operation) to keep memory refreshed.