Intermediate Event Editing Video Tutorials

[Synchysi]

If you're editing the raw hex of the ROM, you wouldn't use LDA #$20 anywhere. It's an assembly mnemonic, and you'd really only use it for documentation purposes or if you start writing actual assembly files, in which case your assembler would convert it to hex and insert it into the ROM.

In this case, A9 20 is the hex translation of LDA #$20.