This mapper is quite similar to Mapper206; however, the registers are scrambled a bit. You should probably study the documentation below for details instead of referencing Mapper206.
Here are Disch's original notes:
========================
= Mapper 112 =
========================
Example Games:
--------------------------
Huang Di
San Guo Zhi - Qun Xiong Zheng Ba
Registers:
---------------------------
Range,Mask: $8000-FFFF, $E001
$8000: [.... .AAA]
A = Address for use with $A000
$A000: [DDDD DDDD]
Data port:
R:0 -> PRG reg 0
R:1 -> PRG reg 1
R:2 -> CHR reg 0
R:3 -> CHR reg 1
R:4 -> CHR reg 2
R:5 -> CHR reg 3
R:6 -> CHR reg 4
R:7 -> CHR reg 5
$E000: [.... ...M]
Mirroring: 0=Vert
1=Horz
CHR Setup:
---------------------------
$0000 $0400 $0800 $0C00 $1000 $1400 $1800 $1C00
+---------------+---------------+-------+-------+-------+-------+
| <R:2> | <R:3> | R:4 | R:5 | R:6 | R:7 |
+---------------+---------------+-------+-------+-------+-------+
PRG Setup:
---------------------------
$8000 $A000 $C000 $E000
+-------+-------+-------+-------+
| R:0 | R:1 | { -2} | { -1} |
+-------+-------+-------+-------+
Categories: INES Mappers, MMC3-like mappers