Platform type
CEX
C as in Consumer/Commerce. Standard device.
It is the most common type installed on commercial PS Vita devices.
No special feature is accessible unless there are QA flags or Diag Console Id.
It cannot load SELF restricted to DEX/Tool. (i.e. CEX allowed bit not set).
Diag
Category of CEX.
It cannot update the System Software and can use SELF files restricted to DEX/Tool.
DEX
D as in Debug. Testing Kit.
It has ability to downgrade the System Software.
It is possible to enter Show Mode with some button combos.
It has preinstalled Debug applications like Debug PS Store, ★Package Installer, ★Mini Debug Settings, ★Debug Settings in Settings, home ★Debug Utility.
Tool
Developer Tool Kit.
It has an additional PC interactive debugger called Communication Processor.
In addition some debuggers are enabled in the kernel as well.
It has an extra LED and mini USB/HDMI in the hardware.
It does not have a battery and is always powered by a 5V Power Adapter. The Communication Processor also has a small coin cell battery for the CP-RTC.
ToolDVT1
Category of Tool.
It uses a different button combo than Tool's in SceSblPostSsMgr.
ToolDVT2
Category of Tool.
It uses a different button combo than Tool's in SceSblPostSsMgr.
ToolRev4
Category of Tool.
It is automatically and infinitely activated.
It uses a different button combo than Tool's in SceSblPostSsMgr.
CEXPrototypeRev2
Unknown prototype.
It uses a different button combo than Tool's in SceSblPostSsMgr.
CEXPrototypeRev7
Unknown prototype.
It uses a different button combo than Tool's in SceSblPostSsMgr.