diff --git a/README.md b/README.md index 4d69a3d..52cbd67 100644 --- a/README.md +++ b/README.md @@ -1106,7 +1106,7 @@ Since we are dealing with a 16-bit address offset it is simpler to break this do int AddressHi = FontAddressHi + (c / 32) ``` -But since the 6502 doesn't have a division instruction we need to use bit-shifts instead. The calculation `c / 32` is the same as `c >> 5`. +But since the 6502 doesn't have a division instruction we need to use bit-shifts instead. The calculation `c / 32` = `c / 2^5` = `c / (1 << 5)` == `c >> 5`. ```c char c = 'D'; // 0x44 @@ -2795,7 +2795,6 @@ That's all folks! Now go write some cool font blitter code. ![font_codepage_437_8x8.png](font_codepage_437_8x8.png) (In progress) - [ ] Double Hi-Res - [ ] PDF of this document (As a work-around use Chrome and Print to PDF) -- [ ] Explains `c/32` = `c / 2^5` = `c / (1 << 5)` = `c >> 5` - [ ] Fix mis-lable: We need to (again) touch up our `PrintChar` entry point at $0310 calling `_DrawChar2` ($034C)