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| -rw-r--r-- | crates/nasm/README.md | 24 |
1 files changed, 19 insertions, 5 deletions
diff --git a/crates/nasm/README.md b/crates/nasm/README.md index 4b4cf50..bc58232 100644 --- a/crates/nasm/README.md +++ b/crates/nasm/README.md @@ -40,6 +40,20 @@ it will also print a warning telling the programmer about this, as this might be unexpected at first. Hence, as a general rule `nasm` will be more noisy than `ca65`, in the hope that the programmer is more aware about the end result. +That being said, `nasm` is at the same time more flexible than `ca65`. For +exemple, the order of declaration for variables, proc's, etc. is not +important. Hence, the following code is valid in `nasm`, but not in `ca65`: + +```asm +.proc foo + ;; 'ca65' will complain that 'Variable' is not known. + lda #Variable + rts +.endproc + +Variable = $00 +``` + ## Mappers By default `nasm` will assume the configuration for an `NROM` mapper, but this @@ -102,8 +116,8 @@ zp_buffer = $20 ; asan:reserve $0F ``` Then the address sanitizer will assume that `zp_buffer = $20..$2F -(included)`. Any access to this reserved range will be considered a -conflict. For example: +(included)`. Any access to this reserved range that is not strictly via +`zp_buffer` will be considered a conflict. For example: ```asm zp_buffer = $20 ; asan:reserve $0F @@ -166,6 +180,6 @@ In NES/Famicom programs you have to advertise on the header whether Working RAM is being used or not (see [byte 6 on the iNES format](https://www.nesdev.org/wiki/INES)). The programmer is expected to set this flag on if PRG RAM is available. If there are memory accesses to PRG RAM -but the programmer did not advertise that on the header flag, then the `nasm` -will error out as it cannot assume that these accesses are valid. This check -will happen regardless of the `-a/--asan` flag. +but the programmer did not advertise that on the header flag, then `nasm` will +error out as it cannot assume that these accesses are valid. This check will +happen regardless of the `-a/--asan` flag. |