NES 2.0 Mapper 328: Difference between revisions
From NESdev Wiki
Jump to navigationJump to search
NewRisingSun (talk | contribs) (Created page with "NES 2.0 mapper 328 is used for the ''Test Ver. 1.01 Dlya Proverki TV Pristavok'' test cartridge. Its UNIF board name is '''UNL-RT-01'''. ==Random number generator or Protecti...") |
(more information about this oddball) |
||
| Line 1: | Line 1: | ||
NES 2.0 mapper 328 is used for the ''Test Ver. 1.01 Dlya Proverki TV Pristavok'' test cartridge. Its UNIF board name is '''UNL-RT-01'''. | NES 2.0 mapper 328 is used for the ''Test Ver. 1.01 Dlya Proverki TV Pristavok'' test cartridge. Its UNIF board name is '''UNL-RT-01'''. There is only 16K of PRG and 2K of CHR and mirroring is hard-wired. | ||
==Random number generator or Protection ($CE80-$CEFF, $FE80-$FEFF, read)== | ==Random number generator or Protection ($CE80-$CEFF, $FE80-$FEFF, read)== | ||
Mask: | Mask: unknown. If what CaH4e3 wrote (quoted below) is accurate, $FFFF. | ||
D~7654 3210 | D~7654 3210 | ||
| Line 10: | Line 10: | ||
It's not known whether the RRR bits are meant to be an actual random number or a protection that can be fooled by returning random numbers. | It's not known whether the RRR bits are meant to be an actual random number or a protection that can be fooled by returning random numbers. | ||
CaH4e3 wrote that the "PRG EPROM has copy protected areas with "weak bits", which is tested at some points of the program. [The random numbers are t]rying to simulate "weak bits" behaviour" | |||
Revision as of 19:09, 31 May 2018
NES 2.0 mapper 328 is used for the Test Ver. 1.01 Dlya Proverki TV Pristavok test cartridge. Its UNIF board name is UNL-RT-01. There is only 16K of PRG and 2K of CHR and mirroring is hard-wired.
Random number generator or Protection ($CE80-$CEFF, $FE80-$FEFF, read)
Mask: unknown. If what CaH4e3 wrote (quoted below) is accurate, $FFFF.
D~7654 3210
---------
1111 RR1R
++-+- Random bits
It's not known whether the RRR bits are meant to be an actual random number or a protection that can be fooled by returning random numbers.
CaH4e3 wrote that the "PRG EPROM has copy protected areas with "weak bits", which is tested at some points of the program. [The random numbers are t]rying to simulate "weak bits" behaviour"
