INES Mapper 040: Difference between revisions

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(Mapper 040 is the only verified LF36.)
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{{DEFAULTSORT:040}}[[Category:iNES Mappers]][[Category:Mappers with fixed-timing cycle IRQs]][[Category:FDS conversion mappers]]
{{DEFAULTSORT:040}}[[Category:iNES Mappers]][[Category:Mappers with fixed-timing cycle IRQs]][[Category:FDS conversion mappers]]
[[iNES Mapper 040]] describes one of Whirlwind Manu's successful attempts (verified cartridge number LF36) at converting the Japanese version of ''Super Mario Bros. 2'' from the [[FDS]] to a cartridge. Their first attempt (cartridge number LE10, [[NES 2.0 Mapper 304]]) [https://archive.org/details/youtube-M2-ovBQW978 hangs on real hardware] after completing level 4-4.
[[iNES Mapper 040]] denotes the NTDEC '''2722''' PCB and imitations, used in several cartridge conversions of the Japanese version of ''Super Mario Bros. 2'':
* ''Super Mario Bros. 2'' from Whirlwind Manu (cartridge code LF36)
* ''Super Mario Bros. II+'' from Hey Sung
* ''1990 Super Mario Bros. 4''
Several other SMB2J conversions running on other mappers reuse the cartridge label from Whirlwind Manu and therefore misleadingly also show an LF36 cartridge code. Hey Sung's version can be distinguished from Whirlwind Manu's by the fact that Whirlwind Manu's does not allow selecting the one of eight starting worlds by holding the D-Pad while pressing START.


This description was produced from the source code of FCEUX and Nestopia.
This description was produced from the source code of FCEUX and Nestopia.
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       +-------+-------+-------+-------+-------+
       +-------+-------+-------+-------+-------+


Like mapper 50, this hardware produces an interrupt 4096 M2 cycles after the IRQ is enabled.
Like [[INES Mapper 050]], this hardware produces an interrupt 4096 M2 cycles after the IRQ is enabled.


The corresponding hardware is a [//forums.nesdev.org/viewtopic.php?p=217200#p217200 CD4020 functioning as a 13-bit counter], and if the software doesn't acknowledge the interrupt for another 4096 cycles it will self-acknowledge.
The corresponding hardware is a [//forums.nesdev.org/viewtopic.php?p=217200#p217200 CD4020 functioning as a 13-bit counter], and if the software doesn't acknowledge the interrupt for another 4096 cycles it will self-acknowledge.

Revision as of 22:10, 26 August 2019

iNES Mapper 040 denotes the NTDEC 2722 PCB and imitations, used in several cartridge conversions of the Japanese version of Super Mario Bros. 2:

  • Super Mario Bros. 2 from Whirlwind Manu (cartridge code LF36)
  • Super Mario Bros. II+ from Hey Sung
  • 1990 Super Mario Bros. 4

Several other SMB2J conversions running on other mappers reuse the cartridge label from Whirlwind Manu and therefore misleadingly also show an LF36 cartridge code. Hey Sung's version can be distinguished from Whirlwind Manu's by the fact that Whirlwind Manu's does not allow selecting the one of eight starting worlds by holding the D-Pad while pressing START.

This description was produced from the source code of FCEUX and Nestopia.

 Registers:
 ---------------------------
 Range,Mask:   $8000-FFFF, $E000

   $8000:  Disable and acknowledge IRQ
   $A000:  Enable IRQ
   $E000:  8 KiB bank mapped at $C000
 
 PRG Setup:
 ---------------------------
 
       $6000   $8000   $A000   $C000   $E000  
     +-------+-------+-------+-------+-------+
     | { 6 } | { 4 } | { 5 } | $E000 | { 7 } |
     +-------+-------+-------+-------+-------+

Like INES Mapper 050, this hardware produces an interrupt 4096 M2 cycles after the IRQ is enabled.

The corresponding hardware is a CD4020 functioning as a 13-bit counter, and if the software doesn't acknowledge the interrupt for another 4096 cycles it will self-acknowledge.

See also