Famicom Network System: Difference between revisions
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(→RF5A18 Modem Controller: Added CPU2 info) |
(FCNS: Fixes the mirroring terminology (previously inverted).) |
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| Line 337: | Line 337: | ||
|+++++++-- (unknown) | |+++++++-- (unknown) | ||
+--------- Mirroring: | +--------- Mirroring: | ||
0 = | 0 = Vertical Mirroring (CIRAM A10 = PPU A10) | ||
1 = | 1 = Horizontal Mirroring (CIRAM A10 = PPU A11) | ||
Read | Read | ||
Revision as of 08:45, 20 January 2021
Memory Map
+================+ $0000 - NES internal RAM | NES internal | | RAM | +----------------+ $0800 | (Mirrors of | | $0000-$07FF) | +================+ $2000 - NES PPU Registers | NES PPU | | Registers | +----------------+ $2008 | (Mirrors of | | $2000-$2007) | +================+ $4000 - NES APU, IO, and Test Registers | NES APU and IO | | Registers | +----------------+ $4018 | NES Test Mode | | Registers | +----------------+ $4020 | (Open Bus) | +================+ $40A0 - Famicom Modem Registers | Famicom Modem | | RF5C66 | | Registers | +----------------+ $40D0 | Famicom Modem | | RF5A18 | | Registers | +----------------+ $40D8 | (Mirror of | | $40D0-$40D7) | +----------------+ $40E0 | (Open Bus) | +----------------+ $4100 | (Open Bus) | +----------------+ $41A0 | (Mirror of | | $40A0-$40FF) | +----------------+ $4200 | (Mirrors of | | $4100-$41FF) | +================+ $5000 - Famicom Modem Kanji ROM | Famicom Modem | | LH5323M1 | | Kanji ROM | +================+ $6000 - Famicom Modem Internal RAM | Famicom Modem | | Internal RAM | +================+ $8000 - Famicom Modem Card Space | | | Card Space | | | +================+ $10000
Known Registers
| Address | Read Has Effect |
Read Has Data |
Write | Owner | Function |
|---|---|---|---|---|---|
| $40A1 | Unknown | Yes | Unknown | RF5C66 | Unknown Function.
Write 76543210 ++++++++-- (unknown) Read 76543210 ++++++++-- Bits exist but function is unknown
|
| $40A2 | Yes | Yes | Unknown | RF5C66 | IRQ Acknowledge, similar to FDS register $4030
Write 76543210 ++++++++-- (unknown) Read 76543210 |||||||+-- Timer Interrupt (1: an IRQ occurred) ||||||+--- Bit exists but function is unknown ||||++---- Bits not shown to exist ++++------ Bits exist but function is unknown
|
| $40A3 | Unknown | No | Yes | RF5C66 | Unknown Function.
Write 76543210 |||||||+-- EXP 6 = $40A3.0 +++++++--- (unknown) Read 76543210 ++++++++-- Bits not shown to exist
|
| $40A4 | Unknown | No | Yes | RF5C66 | Expansion Port Control
Write 76543210 |||||||+-- (unknown) ||||||+--- EXP 5 = !($40A4.1) |||||+---- EXP 4 = !($40A4.2) +++++----- (unknown) Read 76543210 ++++++++-- Bits not shown to exist
|
| $40A5 | Unknown | Yes | Unknown | RF5C66 | Expansion Port Input Data
Write 76543210 ++++++++-- (unknown) Read 76543210 |||||||+-- Input value of EXP 9 ||||||+--- Input value of EXP 8 |||||+---- Input value of EXP 7 |++++----- Bits not shown to exist +--------- Input value of EXP 11
|
| $40A6 | Unknown | Yes | Yes | RF5C66 | M2 Cycle Counter LSB, similar to FDS register $4020
Write 76543210 ++++++++-- Cycle counter reload value (LSB) Read 76543210 ++++++++-- Cycle counter present value (LSB)
|
| $40A7 | Unknown | Yes | Yes | RF5C66 | M2 Cycle Counter MSB, similar to FDS register $4021
Write 76543210 ++++++++-- Cycle counter reload value (MSB) Read 76543210 ++++++++-- Cycle counter present value (MSB)
|
| $40A8 | Unknown | No | Yes | RF5C66 | IRQ Control, similar to FDS register $4022
Write 76543210 |||||||+-- IRQ Repeat Flag ||||||+--- IRQ Enable ++++++---- (unknown) Read 76543210 ++++++++-- Bits not shown to exist
|
| $40A9 | Yes | Yes | Unknown | RF5C66 | Unknown Function.
Write 76543210 ++++++++-- (unknown) Read 76543210 ++++++++-- Bits exist but function is unknown
|
| $40AA | No | Yes | Unknown | RF5C66 | Unknown Function.
Write 76543210 ++++++++-- (unknown) Read 76543210 ++++++++-- Bits exist but function is unknown
|
| $40AB | Yes | No | Yes | RF5C66 | Unknown Function.
Write 76543210 ++++++++-- (unknown) Read 76543210 ++++++++-- Bits not shown to exist
|
| $40AC | Yes | No | Unknown | RF5C66 | Unknown Function.
Write 76543210 ++++++++-- (unknown) Read 76543210 ++++++++-- Bits not shown to exist
|
| $40AD | Unknown | Yes | Yes | RF5C66 | Mirroring Control
Write
76543210
|+++++++-- (unknown)
+--------- Mirroring:
0 = Vertical Mirroring (CIRAM A10 = PPU A10)
1 = Horizontal Mirroring (CIRAM A10 = PPU A11)
Read
76543210
|+++++++-- Bits not shown to exist
+--------- Present value of CIRAM A10
|
| $40AE | Unknown | No | Yes | RF5C66 | Unknown Function.
Write 76543210 |||||||+-- Built-in RAM /CE control: ||||||| 1 = Built-in RAM /CE enabled to go low for reads and writes in the range $6000-7FFF. ||||||| Pin 5C66.28 = 1 at all address ranges. (This pin normally n/c.) ||||||| 0 = Built-in RAM /CE is always high, preventing all reads and writes of the built-in RAM. ||||||| Pin 5C66.28 = 0 at all address ranges. (This pin normally n/c.) +++++++--- (unknown) Read 76543210 ++++++++-- Bits not shown to exist
|
| $40B0 | Yes | No | Yes | RF5C66 | Kanji Graphic ROM Control
Write 76543210 |||||||+-- Kanji ROM Bank Select +++++++--- (unknown) Read 76543210 ++++++++-- Bits not shown to exist
Theory: bit 0 controls 5C66 pin 57 (LH5323M1 Kanji ROM bankswitch bit). |
| $40B1 | Unknown | Yes | Yes | RF5C66 | Modem Control
Write 76543210 |||||||+-- Modem Module pin 29 = $40B1.0, rises slowly, goes low fast ||||||+--- Modem Module pin 32 = $40B1.1, rises slowly, goes low fast |||||+---- Modem Module pin 31 = $40B1.2, rises slowly, goes low fast ||||+----- 5C66-68 to 5A18-27 = !($40B1.3) |||| When set to 1, Exp 18, 19 go high fast, Exp 17 rises slowly |||| Exp 17, 18, 19 do not go low when this bit is cleared. |||+------ Exp 15 = $40B1.4, rises slowly, goes low fast ||+------- Exp 14 = $40B1.5, rises slowly, goes low fast |+-------- Exp 13 = $40B1.6, rises slowly, goes low fast +--------- Exp 12 = $40B1.7, rises slowly, goes low fast Read 76543210 |||||||+-- Input value of Modem Module pin 29 ||||||+--- Input value of Modem Module pin 32 |||||+---- Input value of Modem Module pin 31 ||||+----- Input value of 5C66 pin 63 (normally n/c) |||+------ Input value of EXP 15 ||+------- Input value of EXP 14 |+-------- Input value of EXP 13 +--------- Input value of EXP 12
|
| $40C0 | Unknown | Yes | Yes | RF5C66 | CIC Status, CHR Bank, and RAM Control
Write
76543210
|||||||+-- Pin 5C66.35 = $40C0.0:
||||||| RAM +CE Enable (1 = enabled, 0 = disabled)
||||||+--- Pin 5C66.36 = $40C0.1:
|||||| (This pin normally n/c)
|||||+---- Pin 5C66.37 = $40C0.2:
||||| (This pin normally n/c)
||||+----- Pin 5C66.38 = $40C0.3:
|||| CHR-RAM Bank Select
++++------ (unknown)
Read
76543210
|||||||+-- Input value of pin 5C66.31:
||||||| Host CIC /Reset
||||||+--- Input value of pin 5C66.32:
|||||| Host CIC /Fail
|||||+---- Input value of pin 5C66.33:
||||| Pin 5C66.68 feeds into this pin and into 5A18.27.
||||+----- Input value of pin 5C66.34:
|||| Selected CHR RAM Bank
|+++------ Bits not shown to exist
+--------- Input value of pin 5C66.29:
Filtered Host CIC +Start
|
| $40D0 | Unknown | Yes | Yes | RF5A18 | Unknown Function.
|
| $40D1 | Unknown | Yes | Yes | RF5A18 | Unknown Function.
|
| $40D2 | Unknown | Yes | Yes | RF5A18 | Unknown Function.
|
| $40D3 | Unknown | Yes | Yes | RF5A18 | Unknown Function.
|
| $40D4 | Unknown | Unknown | Yes | RF5A18 | Unknown Function.
Write 76543210 |||||||+-- Exp 17 = $40D4.0 (See also $40B1.3) ||||||+--- Exp 19 = $40D4.1 (See also $40B1.3) |||||+---- Exp 18 = $40D4.2 (See also $40B1.3) +++++----- (unknown) Read 76543210 ++++++++-- (unknown)
|
LH5323M1 ROM
The LH5323M1 is a 256 KB graphics ROM containing primarily kanji data that is mapped at $5000-5FFF. Each index in this range is a 32-byte space containing 16x16 1bpp graphics, usually for a single character, and each read automatically advances to the next byte in the sequence. The space only covers 128 KB and it is suspected that the other 128 KB can be swapped in for additional characters. Writing to $4xB0.0 might control this bankswap behavior. Reading from $4xB0 might reset to the beginning of the 32-byte sequence.
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
RF5C66 Memory Controller
_____
/ \
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
ToneRx Xin, CIC Clock <- / 26 Nintendo RF5C66 77 / -> Exp P3-4
n/c -- / 27 Package QFP-100, 0.65mm pitch 76 / -> Exp P3-5
(n/c) $40AE.0 <- / 28 75 / -> Exp P3-6
Filt'd HostCIC +Start -> / 29 Memory Controller 74 / <- Exp P3-7
Host CIC-12 <- / 30 73 / <- Exp P3-8
/ O 72 / <- Exp P3-9
\ 71 / <- Exp P3-11
Host CIC /Reset -> \ 31 70 / -- GND
Host CIC /Fail -> \ 32 69 / -> 5A18-49
5A18-27, 5C66-68 -> \ 33 68 / -> 5A18-27, 5C66-33 Orientation:
CHR RAM /CE (input) -> \ 34 67 / <> Exp P3-12 --------------------
RAM +CE <- \ 35 66 / <> Exp P3-13 80 51
(n/c) $40C0.1 <- \ 36 65 / <> Exp P3-14 | |
(n/c) $40C0.2 <- \ 37 64 / <> Exp P3-15 .-----------.
CHR RAM /CE <- \ 38 63 / <- $40B1.3 (n/c) 81-|O Nintendo |-50
GND -- \ 39 62 / <> Modem P4-31 | RF5C66 |
Built-in 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 / -> Kanji ROM A17
(GND) ? -> \ 45 56 / -> Kanji ROM A4 Legend:
(GND) ? -> \ 46 55 / -> Kanji ROM A3 ------------------------------
CIRAM A10 <- \ 47 54 / -> Kanji ROM A2 --[RF5C66]-- Power
PPU A11 -> \ 48 53 / -> Kanji ROM A1 ->[RF5C66]<- RF5C66 input
PPU A10 -> \ 49 52 / -> Kanji ROM A0 <-[RF5C66]-> RF5C66 output
Kanji ROM /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, 39, 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 (CIC-11) observed only high (with or without card inserted).
- Seems to be a /reset because it sets pins 52-57 low when this pin is low, and possibly lots of other things.
- Pin 31 (CIC-10) observed only high (with or without card inserted).
- Pin 32 (CIC-15) observed high with card inserted and low with no card inserted or when hot-removed.
- Does not go high when hot-inserted or Famicom reset in low state, only high when card is present at power-on.
- 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 Kanji ROM. (See notes below the LH5323M1 pinout.)
- Pin 15 (Card R/W) is a non-inverted buffer of CPU R/W. This signal connects through the lid switch.
- Pin 26 puts out a 3.58 MHz square wave, ~50% duty. This corresponds to 21.47727 MHz / 6.
- Pin 79 (Exp 2) puts out a 95.95 kHz square wave, 93.7% duty. Clock source unknown.
- Note that this seems similar to FDS serial bitrate.
- Standalone chip can get into a 341.2 kHz mode when touching pin 80, though pulling 80 high or low doesn't correlate.
- Either frequency, the negative pulse width is 650 nsec.
- CIRAM A10 follows PPU A10 by default, suggesting horizontal arrangement / vertical mirroring is default.
RF5A18 Modem Controller
_____
/ \
(U6 RAM) CPU2 A0 <- / 1 100 \ -- GND
(U6 RAM) CPU2 A1 <- / 2 99 \ <> CPU2 D0 (U6 RAM)
(U6 RAM) CPU2 A2 <- / 3 98 \ <> CPU2 D1 (U6 RAM)
(U6 RAM) CPU2 A3 <- / 4 97 \ <> CPU2 D2 (U6 RAM)
(U6 RAM) CPU2 A4 <- / 5 96 \ <> CPU2 D3 (U6 RAM)
(U6 RAM) CPU2 A5 <- / 6 95 \ <> CPU2 D4 (U6 RAM)
(U6 RAM) CPU2 A6 <- / 7 94 \ <> CPU2 D5 (U6 RAM)
(U6 RAM) CPU2 A7 <- / 8 93 \ <> CPU2 D6 (U6 RAM)
+5Vcc -- / 9 92 \ <> CPU2 D7 (U6 RAM)
(U6 RAM) CPU2 A8 <- / 10 91 \ -- +5Vcc
(U6 RAM) CPU2 A9 <- / 11 90 \ -> Modem TXD
(U6 RAM) CPU2 A10 <- / 12 89 \ <- Modem RXD
(U6 RAM) CPU2 A11 <- / 13 88 \ <- CPU A2
(U6 RAM) CPU2 A12 <- / 14 87 \ <- CPU A1
(n/c) CPU2 A13 <- / 15 86 \ <- CPU A0
(n/c) CPU2 A14 <- / 16 85 \ <- /CE (5C66-42)
(n/c) CPU2 A15 <- / 17 84 \ <- P6-1 Lid Switch, Card R/W
GND -- / 18 83 \ <- M2
(n/c) ? <- / 19 82 \ <> Card D7
(U6 RAM) CPU2 R/W <- / 20 81 \ <> Card D6
U6 RAM /CE <- / 21 \
(n/c) ? <- / 22 O /
(test point) CPU2 M2 <- / 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 / <- Tone Rx DV
/ O 72 / <- Tone Rx D8
\ 71 / <- Tone Rx D4
+5Vcc -- \ 31 70 / <- Tone Rx D2
Modem DATA -> \ 32 69 / <- Tone Rx D1
Modem /INT -> \ 33 68 / -> Tone Rx GT Orientation:
Modem /RD <- \ 34 67 / -> Exp P3-19 --------------------
Modem /WR <- \ 35 66 / <- Exp P3-18 80 51
Modem EXCLK <- \ 36 65 / <- Exp P3-17 | |
(n/c) ? <- \ 37 64 / -- +5Vcc .-----------.
Modem AD1 <> \ 38 63 / -> Modem P4-19 81-|O RF5A18 |-50
Modem AD0 <> \ 39 62 / -> Modem P4-21 | Nintendo |
(n/c) ? <- \ 40 61 / -> Modem Audio Enable 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 Reset Legend:
GND -- \ 46 55 / <- Modem P4-23 ------------------------------
(+5Vcc) ? -> \ 47 54 / <- Modem P4-28 --[RF5A18]-- Power
(+5Vcc) ? -> \ 48 53 / <- Modem P4-25 ->[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:
- This chip contains its very own WDC 65C816 CPU, with built-in ROM.
- +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.
- Pin 42 (Exp 16) puts out a 4.92 MHz square wave, ~50% duty. This is 19.6608 MHz / 4.
LH5323M1 Kanji Graphic ROM
_____ Note: Flat spot does not correspond to pin 1.
/ \
n/c -- / 12 11 \ -- n/c
(5C66-52) A0 -> / 13 10 \ -- n/c
CPU D0 <> / 14 9 \ <- A1 (5C66-53)
CPU D1 <> / 15 8 \ <- A2 (5C66-54)
CPU D2 <> / 16 7 \ <- A3 (5C66-55)
GND -- / 17 6 \ -- GND
CPU D3 <> / 18 5 \ <- A5 (CPU A0)
CPU D4 <> / 19 4 \ -- n/c
CPU D5 <> / 20 3 \ <- A6 (CPU A1)
CPU D6 <> / 21 2 \ <- A7 (CPU A2)
CPU D7 <> / 22 Nintendo LH5323M1 1 \ -- n/c
/ Package QFP-44 \
\ 0.8mm pitch /
n/c -- \ 23 44 / <- A8 (CPU A3)
n/c -- \ 24 Kanji Graphic 43 / <- A13 (CPU A8)
(GND) /OE -- \ 25 ROM 42 / <- A16 (CPU A11)
(CPU A6) A11 -> \ 26 41 / <- A4 (5C66-56) Orientation:
(5C66-50) /CE -> \ 27 40 / -- n/c --------------------
GND -- \ 28 39 / -- n/c 33 23
(CPU A7) A12 -> \ 29 38 / -- +5Vcc | |
(CPU A5) A10 -> \ 30 37 / <- A17 (5C66-57 Bankswitch) .-----------.
n/c -- \ 31 36 / <- A15 (CPU A10) 34-| Nintendo O|-22
n/c -- \ 32 35 / -- n/c | CCR-01 |
(CPU A4) A9 -> \ 33 34 / <- A14 (CPU A9) | LH5323M1 |
\ / 44-|O 9528 D |-12
\ / '-----------/
\ / | |
V 01 11
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.
- Pins 13, 9, 8, 7, 41, 37 are controlled by the RF5C66.
- Pins 13, 9, 8, 7, 41 are controlled with auto-increment function.
- The value of these pins increments each M2 falling edge when the CPU is in range $5000-5FFF.
- Pin 37 is a bankswitch, controlled by register $40B0.0
- At reset and when reading from register $40B0, these pins reset to 0.
- The conditions resetting or maintaining the bankswitch pin to 1 are still unknown.
8633 CIC Host
_______ _______
| \_/ |
(Guest CIC-2) Data 0 <> | 1 18 | -- +5Vcc
(Guest CIC-1) Data 1 <> | 2 O 17 | -- n/c
n/c -- | 3 8633 16 | -- n/c
n/c -- | 4 15 | -> /Fail (5C66-32)
n/c -- | 5 CIC 14 | -- n/c
n/c -- | 6 Host 13 | -- n/c
(5C66-26) Clock -> | 7 12 | <- 5C66-30
(Guest CIC-11) /Reset -> | 8 U8 11 | -> +Start (5C66-29)
GND -- | 9 10 | -> /Reset (5C66-31)
|_______________|
8634A CIC Guest
_______ _______
| \_/ |
(Host CIC-2) Data 0 <> | 1 18 | -- +5Vcc
(Host CIC-1) Data 1 <> | 2 O 17 | -- n/c
n/c -- | 3 8634A 16 | ?? GND
n/c -- | 4 15 | -- n/c
n/c -- | 5 CIC 14 | -- n/c
n/c -- | 6 Guest 13 | ?? +5V
(5C66-26) Clock -> | 7 12 | ?? Card-33, n/c in Famicom Network System
(Cap to 5V) /Reset -> | 8 11 | -> +Start (Host CIC-8)
GND -- | 9 10 | -- n/c
|_______________|
- Note: Some assumptions made on CIC chips based on similarity to F411A from Super NES.
8kByte CHR-RAM
_______ _______
| \_/ |
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
|_______________|
8kByte W-RAM
_______ _______
| \_/ |
n/c? -- | 1 28 | -- +5Vcc
CPU A12 -> | 2 O 27 | <- /WR: Card R/W (P6-2 Lid Switch)
CPU A7 -> | 3 26 | <- +CE: RAM +CE
CPU A6 -> | 4 25 | <- CPU A8
CPU A5 -> | 5 LH5268 24 | <- CPU A9
CPU A4 -> | 6 Built-in 23 | <- CPU A11
CPU A3 -> | 7 W-RAM 22 | <- /OE: GND
CPU A2 -> | 8 U5 21 | <- Card A10
CPU A1 -> | 9 20 | <- /CE: Built-in 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
|_______________|
8kByte Modem RAM
_______ _______
| \_/ |
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
Famicom | Modem | Famicom
Network System | Module | Network System
__________
| |
+5Vcc -- | 1 19 | <- 5A18-63
Modem Reset -> | 2 20 | <- Tone Rx GT
Modem AD0 <> | 3 21 | <- 5A18-62
GND -- | 4 22 | -> Tone Rx DV
Modem AD1 <> | 5 23 | -> 5A18-55
Modem RXD <- | 6 24 | <- Tone Rx Xin, from 5C66-26
Modem DATA <- | 7 25 | -> 5A18-53
Modem TXD -> | 8 26 | -- GND
Modem /WR -> | 9 27 | <- 5A18-60
Modem /RD -> | 10 28 | <- 5A18-54
Modem EXCLK -> | 11 29 | <> 5C66-60
+5Vcc -- | 12 30 | <- Modem Audio Enable, 1 = enable
Tone Rx D1 <- | 13 31 | <> 5C66-62 __________________________
Modem /INT <- | 14 32 | <> 5C66-61 | Modem Module |
+5Vcc -- | 15 33 | -- Audio from 2A03 | Orientation |
Tone Rx D2 <- | 16 34 | -- Audio to RF | |
Tone Rx D8 <- | 17 35 | -- GND | 19 _____________ 36 |
Tone Rx D4 <- | 18 36 | -- GND | 1 |___________| 18 |
|________| |________________________|
Note: The modem module uses modem chip Oki MSM6827L and Dual Tone Receiver MC14LC5436P.
P2: Game Card Connector
Card | | Famicom Network System
-----+--+-------------------------
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 Guest CIC-12 in JRA-PAT, n/c in host
34 |??| n/c in JRA-PAT, n/c in host
35 |->| Guest CIC-11 -> Host CIC-8
36 |<>| Guest CIC-1 <> Host CIC-2
37 |<>| Guest CIC-2 <> Host CIC-1
38 |<-| CIC Clock
39 |??| n/c in JRA-PAT, Host has 10k pull-up only.
40 |<-| RAM +CE (n/c in JRA-PAT)
41 |--| GND
42 |--| GND
P3: Expansion Connector
Outside | FNS | Outside _____________________
_________ / Orientation /|
| | /____________________/ |
/IRQ -> | 1 20 | -- +5Vcc |o|_| == |_||_|o|/
(95.94kHz Clock) 5C66-79 <- | 2 19 | -> 5A18-67 \_ _ _ _||_ _ _ _/|
5C66-78 -> | 3 18 | -> 5A18-66 |-| | || HVC-050| |
5C66-77 <- | 4 17 | -> 5A18-65 |-|_| || | |
5C66-76 <- | 5 16 | -> 5A18-42 (4.92MHz Clock) | || | |
5C66-75 <- | 6 15 | <> 5C66-64 | 20 __/__\__ 11 | |
| | |o 1 |______| 10 o| |
5C66-74 -> | 7 14 | <> 5C66-65 | ________________ | |
5C66-73 -> | 8 13 | <> 5C66-66 |/_______________/|| |
5C66-72 -> | 9 12 | <> 5C66-67 ||______________|/ | |
GND -- | 10 11 | <- 5C66-71 | | |
|_______| | ______ | |
|o | | | o| |
\_____|/ |_____|/
