---
title: "Customising Your QL"
type: "article"
slug: "customising-your-ql"
url: "http://localhost/article/customising-your-ql/"
markdown_url: "http://localhost/article/customising-your-ql.md"
published_at: "2026-01-20T21:58:14+00:00"
modified_at: "2026-01-20T21:58:15+00:00"
featured_image:
  url: "http://localhost/wp-content/uploads/2022/04/20230809-041332.jpg"
excerpt: "Here's a very interesting, little known fact about JS and MG ROM QLs (and all Thors too). Included in JS/MG the ROM of a machine is a new keyword called TRA. Now, some people originally thought that this was a long sort after Trace facility. Not so! It's even more fun than a boring old…"
category:
  - name: "CATS Newsletter"
    slug: "cats-newsletter"
    taxonomy: "category"
    url: "http://localhost/category/periodicals/cats-newsletter/"
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/"
publication_r:
  id: 35941
  title: "CATS Newsletter"
  type: "periodical"
  url: "http://localhost/periodical/cats-newsletter/"
volume: "7"
issue: "12"
issues_articles:
  - id: 38909
    title: "CATS v7 n12"
    type: "issue"
    url: "http://localhost/issue/cats-v7-n12/"
pages: "6"
pubdate: "April 1990"
archive_link: false
---

# Customising Your QL

Here’s a very interesting, little known fact about JS and MG ROM QLs (and all Thors too). Included in JS/MG the ROM of a machine is a new keyword called TRA. Now, some people originally thought that this was a long sort after Trace facility. Not so! It’s even more fun than a boring old trace command. What it enables you to do is to customise our QL! Yup, using the TRA command we can set up a new table in memory to hold the text definitions for the error commands.