mirror of
https://github.com/hsoft/collapseos.git
synced 2024-11-17 08:08:07 +11:00
39 lines
1.7 KiB
Markdown
39 lines
1.7 KiB
Markdown
|
# TI-83+/TI-84+
|
||
|
|
|
||
|
|
Texas Instruments is well known for its calculators. Among those, two models
|
||
|
|
are particularly interesting to us because they have a z80 CPU: the TI-83+ and
|
||
|
|
TI-84+ (the "+" is important).
|
||
|
|
|
||
|
|
They lack accessible I/O ports, but they have plenty of flash and RAM. Collapse
|
||
|
|
OS runs on it (see `recipes/ti84`).
|
||
|
|
|
||
|
|
I haven't opened one up yet, but apparently, they have limited scavenging value
|
||
|
|
because its z80 CPU is packaged in a TI-specific chip. Due to its sturdy design,
|
||
|
|
and its ample RAM and flash, we could imagine it becoming a valuable piece of
|
||
|
|
equipment if found intact.
|
||
|
|
|
||
|
|
The best pre-collapse ressource about it is
|
||
|
|
[WikiTI](http://wikiti.brandonw.net/index.php).
|
||
|
|
|
||
|
|
## Getting software on it
|
||
|
|
|
||
|
|
Getting software to run on it is a bit tricky because it needs to be signed
|
||
|
|
with TI-issued private keys. Those keys have long been found and are included
|
||
|
|
in `recipes/ti84`. With the help of the
|
||
|
|
[mktiupgrade](https://github.com/KnightOS/mktiupgrade), an upgrade file can be
|
||
|
|
prepared and then sent through the USB port with the help of
|
||
|
|
[tilp](http://lpg.ticalc.org/prj_tilp/).
|
||
|
|
|
||
|
|
That, however, requires a modern computing environment. As of now, there is no
|
||
|
|
way of installing Collapse OS on a TI-8X+ calculator from another Collapse OS
|
||
|
|
system.
|
||
|
|
|
||
|
|
Because it is not on the roadmap to implement complex cryptography in Collapse
|
||
|
|
OS, the plan is to build a series of pre-signed bootloader images. The
|
||
|
|
bootloader would then receive data through either the Link jack or the USB port
|
||
|
|
and write that to flash (I haven't verified that yet, but I hope that data
|
||
|
|
written to flash this way isn't verified cryptographically by the calculator).
|
||
|
|
|
||
|
|
As modern computing fades away, those pre-signed binaries would become opaque,
|
||
|
|
but at least, would allow bootstrapping from post-modern computers.
|