Keep in mind that some people sometimes use "Mode 20" to refer to the LoROM mapping model, and "Mode 21" to refer to HiROM, although it's technically wrong. D = 0 means LoROM (+ $0), D = 1 means HiROM (+ $1), is used with B and C in case of extended ROMs. A = 0 means SlowROM (+ $0), A = 1 means FastROM (+ $10). The bitmask to use is 001A0BCD, the basic value is $20: In byte $15 in the SNES header (see below for more details), the ROM makeup byte is stored. ExLoROM, ExHiROM and some expansion chips like SA-1 and SDD-1 are said to be able to store up to 8 Megabytes (64 Megabits). One bank holds 256 ($100) pages, so the SNES has $100 (banks) * $100 (pages) = $10000 (65536) pages available.īoth LoROM and HiROM are capable of storing up to 4 Megabytes (32 Megabits) of ROM data. The SNES relies heavily on mapping - for example, without mapping it wouldn't be possible to give all banks of $00 – $3F two pages of WRAM directly at the beginning of the bank. Range does not end with $FF - this is because $FF is the last address of a page, and after this byte a new page begins. You will notice that in the tables below there is no entry in which a certain memory A page is the smallest mappable unit of a Pages are also used for normal PCs (x86/x86-64 architectures) and are hence not exclusive for the SNES. If that's how the machine is supposed to work). Pages are used whenever the machine has to perform mapping tasks (for example, ensuring that address $AABBCC and address $DDBBCC point to the exactly same data, Therefore the SNES has $100 or 256 Banks (start at $00, end at $FF). With three bytes of address space the SNES can address up to 16 Megabytes (2^24 or 1<<24 or 16777216 Bytes = 16384 Kilobytes = 16 Megabytes).īeware that just because the SNES can address 16 Megabytes does not mean it also HAS 16 MB of RAM (here so-called WRAM) - it will be explained in detail later. The bank of the address $AABBCC is $AA (170). Addresses are often shown as hexadecimal values.īank: 64 Kilobytes (65536 or $10000 bytes), basically the most significant byte of the 3 byte address the CPU understands. $ or 0x prefix: the following number is hexadecimal. Before explaining LoROM and HiROM though, we should define some keywords here: Thanks in advance for any advice you can provide.There are two main types of SNES cartridges, the SNES community refers to them as LoROM and HiROM cartridges. Is what I'm trying to do even possible? Ultimately I need the quit hotkey mapped to "(J0)Button 9 + (J0)Button 8". This results in a set to default = disabled This results in only Button 9 being mapped to quit I've attempted a variety of things in the nf file to no avail. A single button press immediately hops the GUI to the next field. Unfortunately the hotkey GUI doesn't seem to take in combinations. I need to map these functions to a button combination (e.g. However, since I'm using an actual SNES controller I have no 'extra' buttons that can be used for this purpose. This means I need to map the hotkeys for quit, save state, and load state to my controller. I'm also using emulationstation and would like to fully interact with the system via controller - i.e. I have a retrolink usb snes controller that is configured and functions properly - no issues there. I am using the April 2nd, 2015 test build found here: I was using v1.53, but switched to this test build due to the inclusion of the hotkey for Quit Snes9x. I've read quite a bit but apologize if I've failed to find the appropriate forum entry that covers this issue. I've spent the past three evenings trying to figure something out and have reached the conclusion it's either not possible or I need to ask for help. Developing something like this can't be easy and its great to have a free option available that works so well. First - thank you for providing a great emulator.
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