Famicom Network System: Difference between revisions
From NESdev Wiki
Jump to navigationJump to search
m (Added blurb about expansion audio.) |
m (Additional note.) |
||
| Line 1: | Line 1: | ||
=Memory Map= | =Memory Map= | ||
* $4xA0-$4xCF: RF5C66 Registers | * $4xA0-$4xCF: RF5C66 Registers | ||
* $4xD0-$ | * $4xD0-$4xD7: RF5A18 Registers | ||
* $4xE0-$4xEF: Unimplemented (pin not hooked up) | * $4xE0-$4xEF: Unimplemented (/CE pin exists but not hooked up) | ||
* $5000-$5FFF: LH5323M1 ROM | * $5000-$5FFF: LH5323M1 ROM | ||
* $6000-$7FFF: Card Bus RAM | * $6000-$7FFF: Card Bus RAM | ||
| Line 299: | Line 299: | ||
- 24, 28, 36, 37, 41, 63 are n/c on the PCB, but have protection diodes from GND, suggesting they may have a function. | - 24, 28, 36, 37, 41, 63 are n/c on the PCB, but have protection diodes from GND, suggesting they may have a function. | ||
- Pins 41 and 42 ranges shown are duplicated at $Cxxx (i.e. ignores /ROMSEL). | - Pins 41 and 42 ranges shown are duplicated at $Cxxx (i.e. ignores /ROMSEL). | ||
- It is unknown how the 5A18 prevents bus conflict at $Cxxx range when it has no known access to /ROMSEL. | |||
- Pins 45-46, when pulled high, causes oscillation on pin 56. | - Pins 45-46, when pulled high, causes oscillation on pin 56. | ||
- Pin 29 is a /reset. It sets pins 52-57 low when this pin is low, and possibly lots of other things. | - Pin 29 is a /reset. It sets pins 52-57 low when this pin is low, and possibly lots of other things. | ||
| Line 326: | Line 327: | ||
+5Vcc -- / 9 92 \ <> U6 RAM D7 | +5Vcc -- / 9 92 \ <> U6 RAM D7 | ||
U6 RAM A8 <- / 10 91 \ -- +5Vcc | U6 RAM A8 <- / 10 91 \ -- +5Vcc | ||
U6 RAM A9 <- / 11 90 \ -> P4-8 | U6 RAM A9 <- / 11 90 \ -> Modem P4-8 | ||
U6 RAM A10 <- / 12 89 \ <- P4-6 | U6 RAM A10 <- / 12 89 \ <- Modem P4-6 | ||
U6 RAM A11 <- / 13 88 \ <- CPU A2 | U6 RAM A11 <- / 13 88 \ <- CPU A2 | ||
U6 RAM A12 <- / 14 87 \ <- CPU A1 | U6 RAM A12 <- / 14 87 \ <- CPU A1 | ||
Revision as of 06:00, 13 November 2020
Memory Map
- $4xA0-$4xCF: RF5C66 Registers
- $4xD0-$4xD7: RF5A18 Registers
- $4xE0-$4xEF: Unimplemented (/CE pin exists but not hooked up)
- $5000-$5FFF: LH5323M1 ROM
- $6000-$7FFF: Card Bus RAM
Known Registers
| Address | Read | Write | Owner | Function |
|---|---|---|---|---|
| $4xA1 | Yes | Unknown | RF5C66 | Unknown Function.
|
| $4xA2 | Yes | Unknown | RF5C66 | Unknown Function.
|
| $4xA3 | No | Yes | RF5C66 | Unknown Function.
|
| $4xA5 | Yes | Unknown | RF5C66 | Unknown Function.
|
| $4xA6 | Yes | Yes | RF5C66 | Unknown Function.
|
| $4xA7 | Yes | Yes | RF5C66 | Unknown Function.
|
| $4xA8 | No | Yes | RF5C66 | Unknown Function.
|
| $4xA9 | Yes | Unknown | RF5C66 | Unknown Function.
|
| $4xAA | Yes | Unknown | RF5C66 | Unknown Function.
|
| $4xAB | No | Yes | RF5C66 | Unknown Function.
|
| $40AC | Yes | Unknown | RF5C66 | Unknown Function.
|
| $4xAD | Yes | Yes | RF5C66 | Unknown Function.
|
| $4xAE | No | Yes | RF5C66 | Unknown Function.
|
| $4xB0 | Unknown | Unknown | RF5C66 | Unknown Function.
|
| $4xB1 | Yes | Yes | RF5C66 | Unknown Function.
|
| $4xC0 | Yes | Yes | RF5C66 | Unknown Function.
|
| $40D0 | Yes | Yes | RF5A18 | Unknown Function.
|
| $40D1 | Yes | Yes | RF5A18 | Unknown Function.
|
| $40D2 | Yes | Yes | RF5A18 | Unknown Function.
|
| $4xD3 | Yes | Yes | RF5A18 | Unknown Function.
|
| $4xD4 | Unknown | Yes | RF5A18 | Unknown Function.
|
Expansion Audio
The Famicom Network System does have expansion audio capabilities. The Famicom audio is routed through the modem module, but nowhere directly to either of the large ASICs. It is unknown if this is used for, or limited to, dial-up modem sounds.
Pinouts
_____
/ \
CPU A0 -> / 1 100 \ -- +5Vcc
CPU A1 -> / 2 99 \ -- n/c
CPU A2 -> / 3 98 \ <> CPU D0
CPU A3 -> / 4 97 \ <> CPU D1
CPU A4 -> / 5 96 \ <> CPU D2
CPU A5 -> / 6 95 \ <> CPU D3
CPU A6 -> / 7 94 \ <> CPU D4
CPU A7 -> / 8 93 \ <> CPU D5
CPU A12 -> / 9 92 \ <> CPU D6
CPU A13 -> / 10 91 \ <> CPU D7
CPU A14 -> / 11 90 \ -- GND
/ROMSEL -> / 12 89 \ <> Card D0
CPU R/W -> / 13 88 \ <> Card D1
M2 -> / 14 87 \ <> Card D2
P6-1 Lid Switch, Card R/W <- / 15 86 \ <> Card D3
(20k resistor to 5Vcc) ? -> / 16 85 \ <> Card D4
/IRQ <- / 17 84 \ <> Card D5
+5Vcc -- / 18 83 \ <> Card D6
n/c -- / 19 82 \ <> Card D7
21.47727MHz Xtal -- / 20 81 \ -- +5Vcc
Xtal -- / 21 \
n/c -- / 22 O /
GND -- / 23 80 / -- n/c
(n/c) Xtal Osc Out <- / 24 79 / -> Exp P3-2
n/c -- / 25 78 / <- Exp P3-3
P4-24, P2-38, CIC-7 <- / 26 Nintendo RF5C66 77 / -> Exp P3-4
n/c -- / 27 Package QFP-100, 0.65mm pitch 76 / -> Exp P3-5
(n/c) ? <- / 28 75 / -> Exp P3-6
CIC-11 w/ filter -> / 29 Memory Controller 74 / <- Exp P3-7
CIC-12 <- / 30 73 / <- Exp P3-8
/ O 72 / <- Exp P3-9
\ 71 / <- Exp P3-11
CIC-10 -> \ 31 70 / -- GND
CIC-15 -> \ 32 69 / -> 5A18-49
5A18-27, 5C66-68 -> \ 33 68 / -> 5A18-27, 5C66-33 Orientation:
CHR RAM /CE (input) -> \ 34 67 / <- Exp P3-12 --------------------
Card RAM +CE <- \ 35 66 / <- Exp P3-13 80 51
(n/c) ? <- \ 36 65 / <- Exp P3-14 | |
(n/c) ? <- \ 37 64 / <- Exp P3-15 .-----------.
CHR RAM /CE <- \ 38 63 / <- ? (n/c) 81-|O Nintendo |-50
GND -- \ 39 62 / <- Modem P4-31 | RF5C66 |
W-RAM /CE ($6000-7FFF) <- \ 40 61 / <- Modem P4-32 100-| GCD 4R O|-31
(n/c) ? /CE ($4xE0-4xEF) <- \ 41 60 / <- Modem P4-29 \-----------'
5A18-85 /CE ($4xD0-4xDF) <- \ 42 59 / -- +5Vcc | |
(GND) ? -> \ 43 58 / -- n/c 01 30
(GND) ? -> \ 44 57 / -> 5323-37
(GND) ? -> \ 45 56 / -> 5323-41 Legend:
(GND) ? -> \ 46 55 / -> 5323-7 ------------------------------
CIRAM A10 <- \ 47 54 / -> 5323-8 --[RF5C66]-- Power
PPU A11 -> \ 48 53 / -> 5323-9 ->[RF5C66]<- RF5C66 input
PPU A10 -> \ 49 52 / -> 5323-13 <-[RF5C66]-> RF5C66 output
LH5323M1 /CE ($5000-5FFF) <- \ 50 51 / -- n/c <>[RF5C66]<> Bidirectional
\ / ??[RF5C66]?? Unknown
\ / f Famicom connection
\ / r ROM chip connection
V R RAM chip connection
Notes:
- +5Vcc pins 18, 59, 81, 100 are all connected together internally.
- GND pins 23, 29, 70, 90 are all connected together internally.
- 43, 44, 45, 46 are GND on the PCB, but have internal protection diodes from GND, suggesting they are logic pins.
- 24, 28, 36, 37, 41, 63 are n/c on the PCB, but have protection diodes from GND, suggesting they may have a function.
- Pins 41 and 42 ranges shown are duplicated at $Cxxx (i.e. ignores /ROMSEL).
- It is unknown how the 5A18 prevents bus conflict at $Cxxx range when it has no known access to /ROMSEL.
- Pins 45-46, when pulled high, causes oscillation on pin 56.
- Pin 29 is a /reset. It sets pins 52-57 low when this pin is low, and possibly lots of other things.
- Pin 16 Pull-up of 20k to 5V is also required in order to avoid triggering reset.
- Pin 16 seems to be related to pin 29. With pin 29 floating and pin 16 pulled high at power on, the chip runs for 5 seconds, then enters reset.
- Tested 10k instead of 20k (per original PCB) on pin 16, found no difference in time or function.
- Pin 69 has a high pulse of 11.9085 usec at any time that register $4xAC has not been read for 12.4892 seconds.
- Each additional 12.4892 seconds generates another pulse.
- It has very repeatable precision, at least 6 figures on each.
- It is not synchronized to M2 or any other inputs.
- Note that 12.4892 sec * 21.47727 MHz = 2^28, with an error of 0.075%. (Nominal would be 12.4986 sec.)
- Note that 11.9085 usec * 21.47727 MHz = 2^8, with an error of 0.093%. (Nominal would be 11.9196 usec.)
- Pins 52-56 drive the address pins of the LH5323M1. (See notes below the LH5323M1 pinout.)
_____
/ \
U6 RAM A0 <- / 1 100 \ -- GND
U6 RAM A1 <- / 2 99 \ <> U6 RAM D0
U6 RAM A2 <- / 3 98 \ <> U6 RAM D1
U6 RAM A3 <- / 4 97 \ <> U6 RAM D2
U6 RAM A4 <- / 5 96 \ <> U6 RAM D3
U6 RAM A5 <- / 6 95 \ <> U6 RAM D4
U6 RAM A6 <- / 7 94 \ <> U6 RAM D5
U6 RAM A7 <- / 8 93 \ <> U6 RAM D6
+5Vcc -- / 9 92 \ <> U6 RAM D7
U6 RAM A8 <- / 10 91 \ -- +5Vcc
U6 RAM A9 <- / 11 90 \ -> Modem P4-8
U6 RAM A10 <- / 12 89 \ <- Modem P4-6
U6 RAM A11 <- / 13 88 \ <- CPU A2
U6 RAM A12 <- / 14 87 \ <- CPU A1
(n/c) ? <- / 15 86 \ <- CPU A0
(n/c) ? <- / 16 85 \ <- /CE (5C66-42)
(n/c) ? <- / 17 84 \ <- P6-1 Lid Switch, Card R/W
GND -- / 18 83 \ <- M2
(n/c) ? <- / 19 82 \ <> Card D7
U6 RAM /WR <- / 20 81 \ <> Card D6
U6 RAM /CE <- / 21 \
(n/c) ? <- / 22 O /
<UNKNOWN>, test point <- / 23 80 / <> Card D5
(GND) ? -> / 24 79 / <> Card D4
(GND) ? -> / 25 78 / -- GND
(GND) ? -> / 26 Nintendo RF5A18 77 / <> Card D3
5C66-33, 5C66-68 -> / 27 Package QFP-100, 0.65mm pitch 76 / <> Card D2
<UNKNOWN> 10k up -> / 28 75 / <> Card D1
<UNKNOWN> 10k up -> / 29 Modem Controller 74 / <> Card D0
n/c -- / 30 73 / <- Modem P4-22
/ O 72 / <- Modem P4-17
\ 71 / <- Modem P4-18
+5Vcc -- \ 31 70 / <- Modem P4-16
Modem P4-7 -> \ 32 69 / <- Modem P4-13
Modem P4-14 -> \ 33 68 / -> Modem P4-20 Orientation:
Modem P4-10 <- \ 34 67 / -> Exp P3-19 --------------------
Modem P4-9 <- \ 35 66 / <- Exp P3-18 80 51
Modem P4-11 <- \ 36 65 / <- Exp P3-17 | |
(n/c) ? <- \ 37 64 / -- +5Vcc .-----------.
Modem P4-5 <- \ 38 63 / -> Modem P4-19 81-|O RF5A18 |-50
Modem P4-3 <- \ 39 62 / -> Modem P4-21 | Nintendo |
(n/c) ? <- \ 40 61 / -> Modem P4-30 100-| GCD 8C O|-31
(n/c) ? <- \ 41 60 / -> Modem P4-27 \-----------'
Exp P3-16 <- \ 42 59 / -> ? (n/c) | |
GND -- \ 43 58 / -> Green LED, active low 01 30
19.6608MHz Xtal -- \ 44 57 / -> Red LED, active low
1k to Xtal -- \ 45 56 / -> Modem P4-2 Legend:
GND -- \ 46 55 / <- Modem P4-23 ------------------------------
(+5Vcc) ? -> \ 47 54 / <- Modem P4-28 --[RF5A18]-- Power
(+5Vcc) ? -> \ 48 53 / <- Modem 4-25 ->[RF5A18]<- RF5A18 input
5C66-69 -> \ 49 52 / <- Switch SW1-4 <-[RF5A18]-> RF5A18 output
n/c -- \ 50 51 / <- Switch SW1-2 <>[RF5A18]<> Bidirectional
\ / ??[RF5A18]?? Unknown
\ / f Famicom connection
\ / r ROM chip connection
V R RAM chip connection
Notes:
- +5Vcc pins 9, 31, 64, 91 are all connected together internally.
- GND pins 18, 43, 46, 78, 100 are all connected together internally.
- 24, 25, 26 are GND on the PCB, but have internal protection diodes from GND, suggesting they are logic pins.
- 47, 48 are +5Vcc on the PCB, but have internal protection diodes to +5Vcc, suggesting they are logic pins.
- 15, 16, 17, 19, 22, 37, 40, 41, 59 are n/c on the PCB, but have protection diodes from GND, suggesting they may have a function.
_____ Note: Flat spot does not correspond to pin 1.
/ \
n/c -- / 12 11 \ -- n/c
(A12) 5C66-52 -> / 13 10 \ -- n/c
CPU D0 <> / 14 9 \ <- 5C66-53 (A13)
CPU D1 <> / 15 8 \ <- 5C66-54 (A14)
CPU D2 <> / 16 7 \ <- 5C66-55 (A15)
GND -- / 17 6 \ -- GND
CPU D3 <> / 18 5 \ <- CPU A0
CPU D4 <> / 19 4 \ -- n/c
CPU D5 <> / 20 3 \ <- CPU A1
CPU D6 <> / 21 2 \ <- CPU A2
CPU D7 <> / 22 Nintendo LH5323M1 1 \ -- n/c
/ Package QFP-44 \
\ 0.8mm pitch /
n/c -- \ 23 44 / <- CPU A3
n/c -- \ 24 Seems like a 43 / <- CPU A8
(GND) /OE -- \ 25 ROM Chip 42 / <- CPU A11
CPU A6 -> \ 26 41 / <- 5C66-56 (A16)
(5C66-50) /CE -> \ 27 40 / -- n/c
GND -- \ 28 39 / -- n/c
CPU A7 -> \ 29 38 / -- +5Vcc
CPU A5 -> \ 30 37 / <- 5C66-57 (A17)
n/c -- \ 31 36 / <- CPU A10
n/c -- \ 32 35 / -- n/c
CPU A4 -> \ 33 34 / <- CPU A9
\ /
\ /
\ /
V
Notes:
- 6 & 28 are connected together internally.
- 17 has no measurable connection to 6 & 28.
- All logic pins have protection diode from pin 17, suggesting this is the true GND.
- Pin 25 also appears as a logic pin with respect to pin 17.
- When pins 25 and 27 are both driven low, the data bus becomes an output. Otherwise it is hi-z. 27 could either be a /CE or W/R.
- Pins 13, 9, 8, 7, 41, 37 are presumably akin to PRG A12 - A17, driven by the 5C66.
- Strangely, the value of these pins increments each M2 falling edge when the CPU is in range $5000-5FFF.
- At reset, these pins are all 0 from the 5C66.
- LH5323M1 ROM chip will see CPU A0-A11 ($xx000 from CPU), ORed with $00xxx supplied from 5C66.
- Example: CPU reads from $5000 repeatedly.
- LH5323M1 ROM chip sees $00000, $01000, $02000, $03000, $04000 ... $1F000, (>>rollover>>) $00000.
- Unknown how but apparently possible to get into range $20000-3FFFF since the ROM has unique data there.
_______ _______
| \_/ |
Card-37 ?? | 1 18 | -- +5Vcc
Card-36 ?? | 2 O 17 | -- n/c
n/c -- | 3 8633 16 | -- n/c
n/c -- | 4 15 | -> 5C66-32
n/c -- | 5 CIC 14 | -- n/c
n/c -- | 6 Host 13 | -- n/c
P4-24, Card-38, 5C66-26 -> | 7 12 | <- 5C66-30
Card-35 ?? | 8 U8 11 | -> 5C66-29 (/Reset)
GND -- | 9 10 | -> 5C66-31
|_______________|
- Seems similar to F411A from Super NES.
_______ _______
| \_/ |
n/c? -- | 1 28 | -- +5Vcc
PPU A12 -> | 2 O 27 | <- PPU /WR
PPU A7 -> | 3 26 | <- +CE: U3=RF5C66 34/38, U4=PPU /A13
PPU A6 -> | 4 25 | <- PPU A8
PPU A5 -> | 5 LH5268 24 | <- PPU A9
PPU A4 -> | 6 CHR 23 | <- PPU A11
PPU A3 -> | 7 RAM 22 | <- /OE: PPU /RD
PPU A2 -> | 8 U3/U4 21 | <- PPU A10
PPU A1 -> | 9 20 | <- /CE: U3=PPU A13, U4=RF5C66 34/38
PPU A0 -> | 10 19 | <> PPU D7
PPU D0 <> | 11 18 | <> PPU D6
PPU D1 <> | 12 17 | <> PPU D5
PPU D2 <> | 13 16 | <> PPU D4
GND -- | 14 15 | <> PPU D3
|_______________|
_______ _______
| \_/ |
n/c? -- | 1 28 | -- +5Vcc
CPU A12 -> | 2 O 27 | <- /WR: Card R/W (P6-2 Lid Switch)
CPU A7 -> | 3 26 | <- +CE: Card RAM +CE
CPU A6 -> | 4 25 | <- CPU A8
CPU A5 -> | 5 LH5268 24 | <- CPU A9
CPU A4 -> | 6 W-RAM 23 | <- CPU A11
CPU A3 -> | 7 22 | <- /OE: GND
CPU A2 -> | 8 U5 21 | <- Card A10
CPU A1 -> | 9 20 | <- /CE: W-RAM /CE
CPU A0 -> | 10 19 | <> Card D7
Card D0 <> | 11 18 | <> Card D6
Card D1 <> | 12 17 | <> Card D5
Card D2 <> | 13 16 | <> Card D4
GND -- | 14 15 | <> Card D3
|_______________|
_______ _______
| \_/ |
n/c? -- | 1 28 | -- +5Vcc
Modem RAM A12 -> | 2 O 27 | <- /WR: Modem RAM /WR
Modem RAM A7 -> | 3 26 | <- +CE: +5Vcc
Modem RAM A6 -> | 4 25 | <- Modem RAM A8
Modem RAM A5 -> | 5 LH5268 24 | <- Modem RAM A9
Modem RAM A4 -> | 6 Modem 23 | <- Modem RAM A11
Modem RAM A3 -> | 7 RAM 22 | <- /OE: GND
Modem RAM A2 -> | 8 U6 21 | <- Modem A10
Modem RAM A1 -> | 9 20 | <- /CE: Modem RAM /CE
Modem RAM A0 -> | 10 19 | <> Modem RAM D7
Modem RAM D0 <> | 11 18 | <> Modem RAM D6
Modem RAM D1 <> | 12 17 | <> Modem RAM D5
Modem RAM D2 <> | 13 16 | <> Modem RAM D4
GND -- | 14 15 | <> Modem RAM D3
|_______________|
P4: Modem Module Edge Connector
_________
| |
+5Vcc | 1 19 | 5A18-63
5A18-56 | 2 20 | 5A18-68
5A18-39 | 3 21 | 5A18-62
GND | 4 22 | 5A18-73
5A18-38 | 5 23 | 5A18-55
5A18-89 | 6 24 | 5C66-26, Card-38, 8633 CIC-7
5A18-32 | 7 25 | 5A18-53
5A18-90 | 8 26 | GND
5A18-35 | 9 27 | 5A18-60
5A18-34 | 10 28 | 5A18-54
5A18-36 | 11 29 | 5C66-60
+5Vcc | 12 30 | 5A18-61
5A18-69 | 13 31 | 5C66-62
5A18-33 | 14 32 | 5C66-61
+5Vcc | 15 33 | Audio from 2A03
5A18-70 | 16 34 | Audio to RF
5A18-72 | 17 35 | GND
5A18-71 | 18 36 | GND
|_______|
P2: Game Card Connector 1 | +5Vcc 2 | +5Vcc 3 | n/c in host 4 | n/c in JRA-PAT, Host has 10k pull-up only. 5 | Card D0 6 | Card D1 7 | Card D2 8 | Card D3 9 | Card D4 10 | Card D5 11 | Card D6 12 | Card D7 13 | Card R/W (P6-2 Lid Switch) 14 | M2 15 | /ROMSEL 16 | CPU A0 17 | CPU A1 18 | CPU A2 19 | CPU A3 20 | CPU A4 21 | CPU A5 | | 22 | CPU A6 23 | CPU A7 24 | CPU A8 25 | CPU A9 26 | CPU A10 27 | CPU A11 28 | CPU A12 29 | CPU A13 30 | CPU A14 31 | n/c in JRA-PAT, Host has 10k pull-up only. 32 | n/c in JRA-PAT, Host has 10k pull-up only. 33 | connected to CIC slave chip in JRA-PAT, n/c in host 34 | n/c in host 35 | 8633 CIC-8 36 | 8633 CIC-2 37 | 8633 CIC-1 38 | P4-24, 8633 CIC-7, 5C66-26 39 | n/c in JRA-PAT, Host has 10k pull-up only. 40 | Card RAM +CE (n/c in JRA-PAT) 41 | GND 42 | GND
P3: Expansion Connector
_________
| |
/IRQ | 1 20 | +5Vcc
5C66-79 | 2 19 | 5A18-67
5C66-78 | 3 18 | 5A18-66
5C66-77 | 4 17 | 5A18-65
5C66-76 | 5 16 | 5A18-42
5C66-75 | 6 15 | 5C66-64
| |
5C66-74 | 7 14 | 5C66-65
5C66-73 | 8 13 | 5C66-66
5C66-72 | 9 12 | 5C66-67
GND | 10 11 | 5C66-71
|_______|
