---
title: "ROM Differences in the TS1500"
type: "article"
slug: "rom-differences-in-the-ts1500"
url: "http://localhost/article/rom-differences-in-the-ts1500/"
markdown_url: "http://localhost/article/rom-differences-in-the-ts1500.md"
published_at: "2026-01-16T21:08:38+00:00"
modified_at: "2026-01-16T21:08:39+00:00"
featured_image:
  url: "http://localhost/wp-content/uploads/2022/04/20230809-041332.jpg"
excerpt: "Some people are a bit unsure about the way in which the TS1500 differs from its predecessors, besides the improved keyboard. I repeat here some information gleaned from previous issues of QZX, particularly the December 1983 issue, about the very minor differences in the ROM. There were only 61 bytes changed at the hex addresses…"
category:
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post_tag:
  - name: "TS 1500"
    slug: "ts1500"
    taxonomy: "post_tag"
    url: "http://localhost/tag/ts1500/"
model:
  - name: "Timex/Sinclair 1500"
    slug: "ts-1500"
    taxonomy: "model"
    url: "http://localhost/model/ts-1500/"
indiv:
  - name: "Alex Burr (K5XY)"
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    taxonomy: "indiv"
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publication: "QZX"
publication_r:
  id: 21219
  title: "QZX"
  type: "periodical"
  url: "http://localhost/periodical/qzx/"
authors_r:
  - name: "Alex Burr (K5XY)"
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volume: "11"
issue: "2"
issues_articles:
  - id: 50200
    title: "QZX v11 n2"
    type: "issue"
    url: "http://localhost/issue/qzx-v11-n2/"
pages: "6-7"
pubdate: "January 1993"
archive_link: false
---

# ROM Differences in the TS1500

Some people are a bit unsure about the way in which the TS1500 differs from its predecessors, besides the improved keyboard. I repeat here some information gleaned from previous issues of QZX, particularly the December 1983 issue, about the very minor differences in the ROM.

There were only 61 bytes changed at the hex addresses 0002-0004; 0006; 0362; 03C6-0401; 16BC; and 18DO. In addition some addresses which had not previously been used were given code.