PR #2967 altered the way ``sdpos_atomic`` was set, causing issues in the
crashdetect/powerpanic recovery offset if the instruction being
recovered happens to contain a comment.
Previously ``sdpos`` was assumed to be a single byte prior to the last
read character. sdpos+1 would thus position the index to the next
instruction. With gcode-filtering in place, sdpos is left just before
the comment, while the actual read position is at the newline. This
causes to parser to resume in the middle of the comment.
Change the value returned by cardreader::get_sdpos() to always return
the last read position, as everybody expects (!!).
This avoids the +1, and correctly sets the resume position to the next
valid instruction without overhead.
- Start saving instructions as the whole PR was >1KB long.
- It turned out the compiler was unable to understand the core skipping
cycle and an ASM version had to be used.
- Add seekSet aware of the G-code filter
This is an extension/optimization of PR #2956.
It uses the cached 512B block buffer to avoid heavy-weight read() in SdBaseFile.
Even though this principle allowed the AVR to skip ~600KB of data within ~5 seconds,
the impact on code base is huge, especially into well proven and long-term stable
parts like reading a file from the SD card.
The sole purpose of this PR is to show/verify the possibility of the AVR CPU
in relation to adding thumbnails into MK3 G-codes.
Moreover, this PR shall not be merged unless the missing/commented features
are restored - especially file seeking and M84 search.
PFW-1175
Remove the conflicting and mostly useless card.paused flag (the printing
is either paused, or not) and switch to isPrintPaused only which
accounts for both cases (SD/USB) correctly.
Fix M27/getStatus to show the current real status of the SD print.
Synchronize the queue on M601, as required to precisely pause the print
at the correct instruction.
Alias M25 to M601, which when combined with PR #1899 fixes issue #1614.
Guard against incorrect usage in M601, M602 and M603.
