INES Mapper 029: Difference between revisions
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The board includes 4x banks worth of full 8KB CHR ram, and 8x 16KB PRG banks. | The board includes 4x banks worth of full 8KB CHR ram, and 8x 16KB PRG banks. | ||
It is hard-wired for vertical mirroring, and contains 8KB of WRAM mounted in the usual place. There is no battery, but pads are present and suitable for such a purpose if anyone were so inclined. There are no bus conflicts. | It is hard-wired for vertical mirroring, and contains 8KB of WRAM mounted in the usual place. There is no battery, but pads are present and suitable for such a purpose if anyone were so inclined. There are no bus conflicts; presumably the other half of the 7420 in the [[PRG RAM circuit]] disables the chip's output on writes. | ||
The board contains logic designed for reprogramming from a CopyNES. If EXP0 and R/W go low, /WR reaches the flash ROM. When EXP0 is high, the internal bankswitching register gets accessed. | The board contains logic designed for reprogramming from a CopyNES. If EXP0 and R/W go low, /WR reaches the flash ROM. When EXP0 is high, the internal bankswitching register gets accessed. | ||
Revision as of 22:08, 16 November 2013
This mapper was allocated on 15-nov-2013 by a mysterious jerkface to implement some homebrew games, including Glider. FCEUX acquired support on r3029.
The example board in question was marked as follows: "Sealie Computing", "RET-CUFROM revD", "2/29/08"
The board includes 4x banks worth of full 8KB CHR ram, and 8x 16KB PRG banks.
It is hard-wired for vertical mirroring, and contains 8KB of WRAM mounted in the usual place. There is no battery, but pads are present and suitable for such a purpose if anyone were so inclined. There are no bus conflicts; presumably the other half of the 7420 in the PRG RAM circuit disables the chip's output on writes.
The board contains logic designed for reprogramming from a CopyNES. If EXP0 and R/W go low, /WR reaches the flash ROM. When EXP0 is high, the internal bankswitching register gets accessed.
Registers:
---------------------------
Range,Mask: $8000-FFFF, $8000
$8000: [...P PPCC]
C = CHR RAM bank
P = PRG ROM bank
PRG Setup:
---------------------------
$8000 $A000 $C000 $E000
+-------------------------------+
| $8000 | { -1} |
+---------------+---------------+
CHR Setup:
---------------------------
$0000 $1000
+-------+-------+
| $8000 |
+-------+-------+
