Difference between revisions of "84PCE:Ports:0028"
From WikiTI
| Line 16: | Line 16: | ||
=== Bit [2] === | === Bit [2] === | ||
| − | Can be written freely (under the usual | + | Can be written freely (under the usual privileged port constraints). |
=== Bit [3] === | === Bit [3] === | ||
Revision as of 13:37, 1 February 2018
Synopsis
Port Number: 0028
Function: Flash Protection Status
Details
Flash is unlocked if both bits 2 and 3 of this port are set.
Bit [0]
Latches value written, no apparent effect.
Bit [1]
Always 0, writes do not latch.
Bit [2]
Can be written freely (under the usual privileged port constraints).
Bit [3]
Can be cleared by writing a 0. Gets cleared any time unprivileged code is executed or port 6 bit 2 is reset. Fetching a flash unlock sequence (F31800F3F3ED7EED56ED3928ED3828CB57) that ends in privileged flash while port 6 bit 2 is set is the only way to set it.
Bits [7:4]
Writes do not latch, no apparent effect.
