---
title: "Z-SI/O RS-232 Interface"
id: 14660
type: "product"
slug: "z-si-o-bare-boards"
url: "http://localhost/product/z-si-o-bare-boards/"
markdown_url: "http://localhost/product/z-si-o-bare-boards.md"
published_at: "2019-11-30T01:19:56+00:00"
modified_at: "2026-03-22T13:20:30+00:00"
author: "David Anderson"
featured_image:
  url: "http://localhost/wp-content/uploads/2019/11/z-sio-scaled.jpg"
excerpt: "Serial interface compatible with the TS 2050/WC 2050 modem. Includes 25-pin RS-232 connector. Uses Intel 8251 USART, the same chip as in the Timex modem, and supports up to 1200 baud modems and 19,200 baud direct connections. Three versions were available: JLO for use with John Oliger disk systems, AERCO for use with the FD-68…"
category:
  - name: "RS232"
    slug: "rs232"
    taxonomy: "category"
    url: "http://localhost/category/hardware/rs232/"
post_tag:
  - name: "Ed Grey Enterprises"
    slug: "ed-grey-enterprises"
    taxonomy: "post_tag"
    url: "http://localhost/tag/ed-grey-enterprises/"
  - name: "TS 2068"
    slug: "ts2068"
    taxonomy: "post_tag"
    url: "http://localhost/tag/ts2068/"
model:
  - name: "Timex/Sinclair 2068"
    slug: "ts-2068"
    taxonomy: "model"
    url: "http://localhost/model/ts-2068/"
genre:
  - name: "Hardware"
    slug: "hardware"
    taxonomy: "genre"
    url: "http://localhost/type/hardware/"
  - name: "RS232"
    slug: "rs232"
    taxonomy: "genre"
    url: "http://localhost/type/rs232/"
company:
  id: 10843
  title: "Ed Grey Enterprises"
  type: "company"
  url: "http://localhost/company/ed-grey-enterprises/"
price: 24.5
date: 1989
rarity: "Uncommon"
related_content:
  - id: 54637
    title: "Z-SI/O Serial Interface Module Installation and Programming"
    type: "document"
    url: "http://localhost/document/z-sio-serial-interface-module-installation-and-and-programming/"
product_reviews:
  - id: 62496
    title: "2068 Telecommunications Notes"
    type: "article"
    url: "http://localhost/article/2068-telecommunications-notes/"
  - id: 62875
    title: "T/S 2068 Serial Cable"
    type: "article"
    url: "http://localhost/article/t-s-2068-serial-cable/"
adverts:
  - publication:
      - id: 26511
        title: "Update October 1988"
        type: "issue"
        url: "http://localhost/issue/ts-2068-up-date-october-1988/"
    advert_page: "1"
  - publication:
      - id: 26493
        title: "Update January 1989"
        type: "issue"
        url: "http://localhost/issue/ts-2068-up-date-january-1989/"
    advert_page: "64"
image_gallery:
  - url: "http://localhost/wp-content/uploads/2019/11/z-sio-scaled.jpg"
companies_products:
  - id: 10843
    title: "Ed Grey Enterprises"
    type: "company"
    url: "http://localhost/company/ed-grey-enterprises/"
---

# Z-SI/O RS-232 Interface

Serial interface compatible with the [TS 2050](http://localhost/product/ts2050-modem/)/[WC 2050](http://localhost/product/westridge-2050-modem/) modem. Includes 25-pin RS-232 connector. Uses [Intel 8251 USART](https://en.wikipedia.org/wiki/Intel_8251), the same chip as in the Timex modem, and supports up to 1200 baud modems and 19,200 baud direct connections.

Three versions were available: JLO for use with John Oliger disk systems, AERCO for use with the FD-68 disk system, and a “stock” version for everything else. The JLO version used ports 9Fh and BFh, the AERCO used D7H and DFh and the stock used the same ports as the TS 2050, 73 and 77h.

Came with a 26 page user manual and a 14 page software development guide that included printer/plotter drivers and terminal emulation listings.