Editing TrackPoint (section)

==Hardware and software development==
Technical documentation of the TrackPoint device is available, which can be useful for keyboard modding and firmware development.
Philips' ''[http://pdf.datasheetcatalog.com/datasheet/philips/PTPM749A.pdf TPM749 Microcontroller with TrackPoint microcode from IBM Product Specification / Data Handbook]'' describes the TrackPoint hardware circuitry and electrical characteristics.
IBM's ''[http://blogs.epfl.ch/icenet/documents/Ykt3Eext.pdf TrackPoint System Version 4.0 Engineering Specification]'' describes how to communicate with and program the TrackPoint device via the PS/2 bus.

There are a few open source keyboard firmwares with TrackPoint support listed below.
These firmwares act as TrackPoint PS/2-to-USB converters, by communicating with the TrackPoint as a PS/2 host and then presenting the TrackPoint data to the USB host as a generic mouse HID device.
# hasu's [https://github.com/tmk/tmk_keyboard tmk_keyboard firmware]
#* Supports middle-button scroll
# frobiac's [https://github.com/frobiac/adnw adnw firmware]
# mtl'l [https://github.com/mtl/tmk_keyboard MX13 code]
#* An extension of hasu's tmk_keyboard firmware
#* Supports many TrackPoint configuration options

Various modules' pinouts are listed on the [[TrackPoint Hardware]] page.