I know about "Chinese Typewriters", the question here is how Chinese was represented in earlier information systems.
For example, Japanese Telegrams were always written in Katakana and many early video games, up to the early 1990s, almost completely relied on Kana for technical reasons. It follows that early Chinese systems may also have relied on Pinyin or Bopomofo (in Taiwan). Can sb. confirm this?
(The following is not part of the question, but facts I discovered and want to share here although they don't amount to answers themselves.)
For what it's worth, this page https://classictech.wordpress.com/computer-companies/acer-groupmultitech-electronics-inc-sunnyvale-calif/ claims that the MPF-II-C from 1982 was the first microcomputer to be capable of handling Chinese characters.
A commenter linked to http://www.njstar.com/cms/chinese-commercial-telegraph-code-lookup, it contains the following valuable information regarding the CCC:
There are total of 9297 Chinese Commercial Codes defined, of which 2593 codes represent different Chinese characters in Mainland and in Taiwan/Hong Kong. Codes below 7902 are caused by the fact of Mainland Chinese character simplification. Such as ccc:0948 --> 国 U+56FD (CN) / 國 U+570B (TW/HK). Due to un-coordinated extension of original codes, codes above 7902 can respresent totally different characters in Mainland and in Taiwan/Hong Kong. Such as ccc:9154 --> 舺 U+823A (CN) / 螵 U+87B5 (TW/HK)