Memory Map of fx-991DEX
ROM Window (0:0000h - 0:FE47h)
An image of segment 0 of the ROM. Writing to this part of memory has no effect.
Note: The last few unused bytes are all 0xff
RAM (1:0000h - 1:FFFFh)
Should be writable RAM.
Everything after this is in segment 1 not 0!
input buffer
- Address [0xd1d0 .. 0xd297]
- Size: 200 bytes
cache area
- Address [0xd298 .. 0xd35f]
- Size: 200 bytes
random seed
- Address [0xd360 .. 0xd368]
- Size: 8 bytes
- Note: this is initially filled with 0s but gets changed when you run Ran# or anything random related
- Note: this doesn't get cleared on a warm start (pressing [ON])
unstable character
- Address [0xd368 .. 0xd36a]
- Size: 2 bytes
- Note: increments everytime the cursor changes it's state between on and off (stops counting while you're typing)
- Note: also doesn't get cleared
normal stack
- Address [0xf000 decreasing]
- Size: undefined
- Note: the initial SP holds the value 0xf000
- Note: the SP is 0xedde most of the time