| Company | Namco |
| Games | 20 in NesCartDB |
| Complexity | ASIC |
| Boards | 11xF0, 111F0S |
| Pinout | Namcot 163 family pinout |
| PRG ROM capacity | 512K |
| PRG ROM window | 8Kx3 + 8K fixed |
| PRG RAM capacity | 8K |
| PRG RAM window | 8K |
| CHR capacity | 256K |
| CHR window | 1Kx8 (PT) + 1Kx4 (NT) |
| Nametable mirroring | arbitrary, up to 226 source nametables |
| Bus conflicts | No |
| IRQ | CPU cycle counter |
| Audio | Yes |
| iNES mappers | 019 |
iNES Mapper 019 is used to denote Famicom boards bearing the Namco 129 and Namco 163 ASICs. These chips contain 128 bytes of internal RAM that can be used either for expansion audio or, together with a battery, for 128 bytes of save RAM. Games may also come with the regular 8 KiB of additional battery-backed WRAM mapped into CPU address space at $6000-$7FFF.
In NES 2.0, the 128 bytes of internal chip RAM are not included in the PRG-RAM and PRG-NVRAM fields. NES 2.0 Mapper 19 ROM images therefore either have:
The NES 2.0 submapper is used to specify the mixing resistor that determines the relative volume of the expansion audio channels against the APU's audio channels:
| INES Mapper 019 submapper table | ||
|---|---|---|
| Submapper # | Meaning | Note |
| 0 | Default | Expansion sound volume unspecified |
| 1 | Deprecated | Internal 128b RAM is battery backed, no external PRG-RAM is present.
No expansion sound. (Equivalent to submapper 2 with 0 in PRG-NVRAM field.) |
| 2 | No expansion sound | |
| 3 | N163 expansion sound: 11.0-13.0 dB louder than NES APU | |
| 4 | N163 expansion sound: 16.0-17.0 dB louder than NES APU | |
| 5 | N163 expansion sound: 18.0-19.5 dB louder than NES APU | |
| Name | Chip | Battery | WRAM | Expansion Audio | NES 2.0 Submapper |
|---|---|---|---|---|---|
| Battle Fleet | 163 | Yes | No | No | 2 |
| Dragon Ninja | 163 | No | No | No | 2 |
| Digital Devil Story: Megami Tensei II | 163 | Yes | Yes | Yes | 3 |
| Dokuganryuu Masamune | 163 | Yes | No | No | 2 |
| Erika to Satoru no Yume Bouken | 163 | No | No | Yes | 5 |
| Famista '90 | 163 | Yes | No | No | 2 |
| Final Lap | 163 | No | No | Yes | 3 |
| Hydlide 3: Yami kara no Houmonsha | 163 | Yes | No | No | 2 |
| Juvei Quest | 163 | Yes | Yes | No | 2 |
| Kaijuu Monogatari | 163 | Yes | No | No | 2 |
| King of Kings | 163 | Yes | Yes | Yes | 5 |
| Mappy Kids | 163 | No | No | Yes | 5 |
| Mindseeker | 163 | Yes | No | No | 2 |
| Namco Classic | 163 | No | No | No | 2 |
| Namco Classic II | 163 | No | No | Yes | 3 |
| Rolling Thunder | 163 | No | No | Yes | 4 |
| Sangokushi: Chuugen no Hasha | 163 | Yes | Yes | Yes | 5 |
| Sangokushi II: Haou no Tairiku | 163 | Yes | Yes | Yes | 3 |
| Star Wars | 129 | No | No | No | 2 |
| Youkai Douchuuki | 163 | No | No | Yes | 5 |
These ASICs have the unusual ability to select the internal 2 KB nametable RAM as a CHR bank page, allowing it to be used as CHR RAM in combination with the existing CHR ROM.
The 163 has 19 registers within $4800-$5FFF and $8000-$FFFF. Each register occupies a range of $800 bytes, so $4800-$4FFF all refers to one register, $5000-$57FF all refers to another register, and so on.
See Namco 163 audio.
7 bit 0 ---- ---- IIII IIII |||| |||| ++++-++++- Low 8 bits of IRQ counter
7 bit 0 ---- ---- EIII IIII |||| |||| |+++-++++- High 7 bits of IRQ counter +--------- IRQ Enable: (0: disabled; 1: enabled)
| Value CPU writes | Behavior |
|---|---|
| $00-$DF | Always selects 1KB page of CHR-ROM |
| $E0-$FF | If enabled by bit in $E800, use the NES's internal nametables (even values for A, odd values for B) |
| Write to CPU address | 1KB CHR bank affected | Values ≥ $E0 denote NES NTRAM if |
|---|---|---|
| $8000-$87FF | $0000-$03FF | $E800.6 = 0 |
| $8800-$8FFF | $0400-$07FF | $E800.6 = 0 |
| $9000-$97FF | $0800-$0BFF | $E800.6 = 0 |
| $9800-$9FFF | $0C00-$0FFF | $E800.6 = 0 |
| $A000-$A7FF | $1000-$13FF | $E800.7 = 0 |
| $A800-$AFFF | $1400-$17FF | $E800.7 = 0 |
| $B000-$B7FF | $1800-$1BFF | $E800.7 = 0 |
| $B800-$BFFF | $1C00-$1FFF | $E800.7 = 0 |
| $C000-$C7FF | $2000-$23FF | always |
| $C800-$CFFF | $2400-$27FF | always |
| $D000-$D7FF | $2800-$2BFF | always |
| $D800-$DFFF | $2C00-$2FFF | always |
It is believed, but untested, that a game could add a normal SRAM and use it in lieu of the nametable RAM; if so, a game would be able to get 4-screen mirroring and many more pages of CHR-RAM.
7 bit 0 ---- ---- AMPP PPPP |||| |||| ||++-++++- Select 8KB page of PRG-ROM at $8000 |+-------- Disable sound if set +--------- Pin 22 (open collector) reflects the inverse of this value, unchanged by the address bus inputs.
7 bit 0
---- ----
HLPP PPPP
|||| ||||
||++-++++- Select 8KB page of PRG-ROM at $A000
|+-------- Disable CHR-RAM at $0000-$0FFF
| 0: Pages $E0-$FF use NT RAM as CHR-RAM
| 1: Pages $E0-$FF are the last $20 banks of CHR-ROM
+--------- Disable CHR-RAM at $1000-$1FFF
0: Pages $E0-$FF use NT RAM as CHR-RAM
1: Pages $E0-$FF are the last $20 banks of CHR-ROM
7 bit 0 ---- ---- B.PP PPPP | || |||| | ++-++++- Select 8KB page of PRG-ROM at $C000 +--------- Pin 44 reflects this value.
7 bit 0 ---- ---- KKKK DCBA |||| |||| |||| |||+- 1: Write-protect 2kB window of external RAM from $6000-$67FF (0: write enable) |||| ||+-- 1: Write-protect 2kB window of external RAM from $6800-$6FFF (0: write enable) |||| |+--- 1: Write-protect 2kB window of external RAM from $7000-$77FF (0: write enable) |||| +---- 1: Write-protect 2kB window of external RAM from $7800-$7FFF (0: write enable) ++++------ Additionally the upper nybble must be equal to b0100 to enable writes
Any value outside of the range $40-$4E will cause all PRG RAM to be read-only.
Also see Namco 163 audio.
The IRQ is a 15-bit CPU cycle up-counter. $5000 and $5800 provide direct access to the counter itself (i.e., this isn't a reload value). Games can read and write to these registers in realtime.
The IRQ counter increments on each CPU cycle. Upon reaching $7FFF, an IRQ is fired, and it stops counting. Writing to $5000 or $5800 will acknowledge any pending IRQs.
All of the below are in Japanese:
Categories: Mappers using $4020-$5FFF, Mappers with CHR ROM and CHR RAM, ASIC mappers, In NesCartDB, Mappers with single-screen mirroring, Mappers with ROM nametables, Mappers with cycle IRQs