It is possible to read the state of the flags with basic

[boriel]

No, you need to use assembler (in fact it's difficult even in assembler to read the entire flag without changing them). You can get them for example:

Code:

DIM flags as Ubyte

#define save_flags \
    ASM \
    push af \
    pop hl \
    ld a, l \
    ld (._flags), a \
    END ASM

REM Now you can save flags at any moment with this macro
...
LET a = 5: save_flags: PRINT "Flags: "; flags

You can also create a function if you feel more comfortable, but will require also assembler, and I'm not sure if flags will be altered when jumping
into the function:

Code:

function fastcall get_flags as Ubyte
  ASM
  push af
  pop hl
  ld a, l
  END ASM
end function

PRINT "Flags: "; get_flags

Perhaps you might find this useful??