---
title: "Bits and Bytes"
type: "article"
slug: "bits-and-bytes-2"
url: "http://localhost/article/bits-and-bytes-2/"
markdown_url: "http://localhost/article/bits-and-bytes-2.md"
published_at: "2021-02-07T16:29:10+00:00"
modified_at: "2024-05-26T14:06:40+00:00"
featured_image:
  url: "http://localhost/wp-content/uploads/2022/04/20230809-041332.jpg"
excerpt: "Differences in pull-up resistors between Z80 and Z80A/Z80B. Spectrum software may run on 2068. Bug in 2068 gives invalid value for INT(-65536). Monitor tips for QL."
category:
  - name: "QZX"
    slug: "qzx"
    taxonomy: "category"
    url: "http://localhost/category/periodicals/qzx/"
post_tag:
  - name: "QL"
    slug: "ql"
    taxonomy: "post_tag"
    url: "http://localhost/tag/ql/"
  - name: "TS 2068"
    slug: "ts2068"
    taxonomy: "post_tag"
    url: "http://localhost/tag/ts2068/"
model:
  - name: "Sinclair QL"
    slug: "sinclair-ql"
    taxonomy: "model"
    url: "http://localhost/model/sinclair-ql/"
  - name: "Timex/Sinclair 2068"
    slug: "ts-2068"
    taxonomy: "model"
    url: "http://localhost/model/ts-2068/"
publication: "QZX"
publication_r:
  id: 21219
  title: "QZX"
  type: "periodical"
  url: "http://localhost/periodical/qzx/"
volume: "6"
issue: "4"
issues_articles:
  - id: 26567
    title: "QZX v6 n4"
    type: "issue"
    url: "http://localhost/issue/qzx-v6-n4/"
pages: "10"
pubdate: "March 1988"
archive_link: false
volumeissue: "v6n4"
---

# Bits and Bytes

Differences in pull-up resistors between Z80 and Z80A/Z80B. Spectrum software may run on 2068. Bug in 2068 gives invalid value for INT(-65536). Monitor tips for QL.