Editing IBM PCjr (section)

===Keyboard / Lightpen===
[[File:Living Computer Museum IMG 0034 (9639456054) (cropped).jpg|thumb|The wireless PCjr keyboard]]
The original keyboard included with the PCjr was a wireless design using infrared line-of-sight communication, which IBM initially marketed as the "Freeboard."<ref>{{Cite book|url=https://books.google.com/books?id=9eJxx_ZGKngC&q=ibm%20freeboard&pg=PA25|title=PC Mag|date=1984-04-17|publisher=Ziff Davis, Inc.|language=en}}</ref> This is a [[chiclet keyboard]] with small, flat, calculator style plastic keycaps. The keycaps are blank, with the labels printed between keys so that [[Keyboard layout|overlays]] can be used.{{r|halfhill198401}} The PCjr keyboard has 62 keys rather than the 83 of the PC keyboard, and the remaining keys must be entered by holding a modifier key.{{r|halfhill198401}}{{r|pollack19831102}}

For infrared wireless operation, the keyboard is powered by four AA cells. Certain types of room lighting can cause interference with the infrared keyboard sensor,<ref name="nichols20140322">{{cite web|author=Nichols, Shaun|date=March 22, 2014|title=IBM PCjr STRIPPED BARE: We tear down the machine Big Blue would rather you forgot|url=https://www.theregister.co.uk/2014/03/22/ibm_pcjr_stripped_bare_still_mediocre_after_all_these_years/|access-date=April 1, 2014|website=The Register}}</ref> and multiple keyboards cannot be used wirelessly in the same room without problems.<ref name="lgr20110117">{{cite AV media|url=https://www.youtube.com/watch?v=MbSto9irCoE |archive-url=https://ghostarchive.org/varchive/youtube/20211212/MbSto9irCoE| archive-date=2021-12-12 |url-status=live|title=LGR - Experiencing The IBM PCjr Chiclet Keyboard|date=January 17, 2011|people=Lazy Game Reviews|publisher=YouTube}}{{cbignore}}</ref>

IBM sold a cable which could be plugged in between the keyboard and computer if the user wanted a more reliable connection, which also eliminated the need for batteries, since the keyboard IR receiver is automatically disabled when the cord is attached to the computer.

The chiclet design was not well received, and in 1984 IBM began shipping a new design, still wireless, but using more conventionally shaped keycaps.{{r|halfhill198410}}

The PCjr also has a [[light pen]] port. Besides being used for a light pen (a rarely purchased option), this port can be used in combination with the serial port to supply voltage to a [[Mouse Systems]] optical mouse of the same design as those for [[Sun Microsystems|Sun workstations]].