---
title: "La Page du Sinclair QL"
type: "article"
slug: "la-page-du-sinclair-ql-4"
url: "http://localhost/article/la-page-du-sinclair-ql-4/"
markdown_url: "http://localhost/article/la-page-du-sinclair-ql-4.md"
published_at: "2026-03-10T12:58:08+00:00"
modified_at: "2026-03-10T12:58:08+00:00"
featured_image:
  url: "http://localhost/wp-content/uploads/2022/04/20230809-041332.jpg"
excerpt: "In the previous issue of SIN, we saw that the ROM of the American QL contained some undocumented commands. We discussed the WHEN ... END WHEN sequence, which could be used to detect any event or to handle errors (with ERROR and REPORT)."
category:
  - name: "SIN"
    slug: "sin"
    taxonomy: "category"
    url: "http://localhost/category/periodicals/sin/"
post_tag:
  - name: "QL"
    slug: "ql"
    taxonomy: "post_tag"
    url: "http://localhost/tag/ql/"
  - name: "Type-in program"
    slug: "type-in-program"
    taxonomy: "post_tag"
    url: "http://localhost/tag/type-in-program/"
model:
  - name: "Sinclair QL"
    slug: "sinclair-ql"
    taxonomy: "model"
    url: "http://localhost/model/sinclair-ql/"
indiv:
  - name: "Real Gagnon"
    slug: "real-gagnon"
    taxonomy: "indiv"
    url: "http://localhost/indiv/real-gagnon/"
publication_r:
  id: 52924
  title: "SIN"
  type: "periodical"
  url: "http://localhost/periodical/sin/"
authors_r:
  - name: "Real Gagnon"
    slug: "real-gagnon"
    taxonomy: "indiv"
    url: "http://localhost/indiv/real-gagnon/"
issue: "9"
issues_articles:
  - id: 52943
    title: "SIN n9 Apr-May 1986"
    type: "issue"
    url: "http://localhost/issue/sin-n9-apr-may-1986/"
pages: "13-14"
pubdate: "April-May 1986"
archive_link: false
---

# La Page du Sinclair QL

In the previous issue of SIN, we saw that the ROM of the American QL contained some undocumented commands. We discussed the WHEN … END WHEN sequence, which could be used to detect any event or to handle errors (with ERROR and REPORT).