Changes in
lcd_implementation_drawmenu_sdfile
and
lcd_implementation_drawmenu_sddirectory
seem to save the most.
Change in memory:
Flash: -72 bytes
SRAM: 0 bytes
There are only 3 possible values. No need to check for two of them
to rule of the last value. Instead simply check for the last value only.
Change in memory:
Flash: -16 bytes
SRAM: 0 bytes
Found these a few months ago when I was trying some other optimization. Don't want to make a PR just for this, so I'll just slide it here in this existing PR.
The old implementation would fail if the message was in progmem at address 0xffff or 0x0000 (both unlikely). It would also fail if the eeprom was initialized to some other random value, which could have been dangerous when displayed as a full screen message.
These variables only range from 0 to 255
For the menus we currently need to convert fanSpeed to int16_t.
Change in memory:
Flash: -160 bytes
SRAM: -2 bytes
This fixes the spurious feedback when rotating the knob
because lcd_update is called much often than the interval
at which the lcd rendering is updated
Change in memory
Flash: -88 bytes
SRAM: -9 bytes
Valid values range from -100 to 100. Storing this value as four bytes
(int32_t) is not efficient.
Instead we can store G80 user input temporarily as int32_t and check
if the value is within the allowed range. If it is, then we convert the
int32_t (4 bytes) to int8_t (1 byte).
Change in memory:
Flash: -78 bytes
SRAM: 0 bytes
This way doesn't add any more flash memory.
Calculating the string length or checking for a null byte
will end up increasing flash consumption overall.
This gets rid of float conversion.
We just need to check the 6th character when M862 is detected. This
character gives us the digit after the dot.
Change in memory:
Flash: -20 bytes
SRAM: 0 bytes
For non-time critical code it is more effcient to call a function
rather inlining each division operation.
Change in memory:
Flash: -122 bytes
SRAM: 0 bytes
Noticed this when exploring another optimisation
By specification exactly which overloaded function to use
we save some memory
Seems to have something to do with doing arithmetic in the function argument
Change in memory:
Flash: -156 bytes
SRAM: 0 bytes
There is no need to repeat:
lcd_update_enable(true);
lcd_update(2);
Also lcd_clear() is redundant because lcd_update(2) will clear the LCD
Change in memory:
Flash: -16 bytes
SRAM: 0 bytes