C64Nano

The C64Nano is a port of some MiST and MiSTer core components for the C64:

Board	FPGA	support	Note
Tang Nano 20k	GW2AR	HDMI / LCD	Dualshock or 2nd D9 Joystick via MiSTeryShield20k spare header
Tang Primer 25K	GW5A-25	HDMI	no Dualshock, no Retro D9 Joystick, no MIDI
Tang Mega NEO 60k Dock	GW5AT-60	HDMI / LCD	twin Dualshock
Tang Mega 138k Pro	GW5AST-138	HDMI / LCD	twin Dualshock
Tang Console 60K NEO	GW5AT-60	HDMI / LCD	twin Dualshock, no Retro D9 Joystick
Tang Console 138K NEO	GW5AST-138	HDMI / LCD	twin Dualshock, no Retro D9 Joystick

This project relies on a MPU being connected to the FPGA. --> MiSTle-Dev wiki <--

Original C64 core by Peter Wendrich and c1541 by darfpga.
All HID components and MPU firmware by Till Harbaum

Features:

• support of Core load from FLASH or USB pendrive (Console SDcard + USB)
• PAL 720x576p@50Hz or NTSC 720x480p@60Hz HDMI Video and Audio Output
• TFT-LCD module 800x600 SH500Q01Z + Speaker support
• USB Keyboard
• USB Joystick or USB Gamepad
• USB Mouse as c1351 Mouse emulation
• USB Gamepad Stick as Paddle Emulation
• USB XBOX 360 Controller as Joystick or Paddle
• 2 x legacy D9 Joystick (Atari / Commodore digital type)
• Joystick emulation on Keyboard Numpad
• Emulation of C64GS Cheetah Annihilator Joystick 2nd Trigger Button (Pot X/Y)
• emulated 1541 Diskdrive on FAT/extFAT microSD card with parallel bus Speedloader Dolphin DOS 2. GER manual
• C1541 DOS ROM selection
• Cartridge ROM (*.CRT) loader
• Direct BASIC program (*.PRG) injection loader
• Tape (*.TAP) image loader as C1530 Datasette
• Loadable 8K Kernal ROM (*.BIN)
• REU (*.reu) image loader
• VIC-II revision and 6526 / 8521 selection
• SID revision 6581 or 8580 selectable
• 2nd dual SID Option and loadable Filter curves
• emulated RAM Expansion Unit (REU) or GeoRAM
• On Screen Display (OSD) for configuration and loadable image selection (D64/G64/CRT/PRG/BIN/TAP/FLT)
• Physical MIDI-IN and OUT
• RS232 Serial Interface VIC-1011 or UP9600 mode to Tang onboard USB-C serial port or external hw pin.
• Swiftlink-232 6551 WIFI Modem Interface to FPGA-Companion up to 38400 Baud
• Freezer support (e.g. Action Replay)
• external IEC device (C1541 Floppy / IEC Printer etc.)
• DigiMax four channel audio DAC ($DE00 /$DF00)
• EasyFlash CRT Save (for enhanced Games that support write to Flash as gameplay progress storage)

Installation

The installation of C64 Nano on the Tang Nano 20k board can be done using a Linux PC or a Windows PC (Instruction).

c64 Nano on Tang Primer 25K

See Tang Primer 25K. PMOD TF-CARD V2 is required !

c64 Nano on Tang Mega NEO 60k Dock

See Tang Mega 60K NEO

c64 Nano on Tang Mega 138k Pro

See Tang Mega 138K Pro

c64 Nano on Tang Console 60k / 138k NEO

See Tang Console 60K / 138k NEO

c64 Nano with LCD and Speaker

See Tang Nano LCD

emulated Diskdrive c1541

Emulated 1541 on a regular FAT/exFAT formatted microSD card including parallel bus Speedloader Dolphin DOS 2.0. Add D64 or G64 images as you like and insert card in TN slot. LED 0 acts as Drive activity indicator.

C1541 DOS ROM can be selected from OSD (default Dolphin DOS 2.0, CBM DOS, SpeedDos Plus or JiffyDOS) In case a program don't load correctly select via OSD the factory default CBM DOS an give it a try.

Cartridge ROM Loader (.CRT)

Cartridge ROM can be loaded via OSD file selection.
Also EasyFlash save game progress images are loaded via this item.

EasyFlash Cartridge Save (.CRT)

Saving game progress for EasyFlash cartridge images is now the de facto standard. Progress is written directly into the *.CRT file, so the image is modified in place (rewritten). It is strongly recommended to keep a backup copy in case the file becomes corrupted.

Workflow:

1. Load your game via CRT ROM: as usual, for example caren_priorart_ef.crt or any other EasyFlash-enabled game.
2. Perform the in-game save-to-CRT process (this is game-specific). The game will program selected blocks of the two emulated AM29F040B flash chips to store progress.
3. Press Save EZFLASH:. The core writes the updated EasyFlash image, including the modified save blocks, back to the SD card (for example as caren_priorart_ef.crt).

To resume a saved game, load it again via CRT ROM: and use the in-game load/continue function.

This feature behaves differently than on MiSTer: MiSTer rewrites the CRT image in Linux userspace and creates a different file. Here, the rewrite is done directly by the Mistle C64 core in HDL, and the original CRT file is overwritten.

BASIC Program Loader (.PRG)

A BASIC Program *.PRG file can be loaded via OSD file selection. Auto RUN after load can be disabled via OSD.

Tape Image Loader (*.TAP)

A Tape *.TAP file can be loaded via OSD file selection In order to start a tape download choose C64 CBM Kernal (mandatory as Dolphin DOS doesn't support Tape). Best to save Kernal OSD selection via Save settings.

The file is loaded automatically as soon as TAP file selected via OSD (no need to press PLAY TAPE button) in case no TAP had been previously selected. As mentioned screen will blank for several seconds and then display briefly the filename of the to be loaded file. It will blank shortly afterwards again till load completed and take a lot of time... For Tape unload use OSD TAP selection No Disk and Reset or System Cold Boot

Kernal Loader (.BIN)

The build-in Dolphin Kernal is the power-up default C64 Kernal with an excellent C1541 speedloader.

In general Kernal ROM files *.BIN can be loaded via OSD selection. Copy a 8K C64 Kernal ROM .BIN to your sdcard and rename it to c64kernal.bin as default boot Kernal. Prevent Kernal load by OSD Kernal BIN selection No Disk and Save settings and do a power-cyle of the board. In this case the build-in Dolphin Kernal will by default be used after next power cycle.

SID Filter Curve (.FLT)

Custom filter curves can optionally be loaded via OSD.

Filter examples and references: https://www.telnetbbsguide.com/bbs/software/image-bbs/

To disable filter-curve loading, set OSD Kernal FLT to No Disk, select Save settings, and power-cycle the board.

Ram Expansion Unit (.REU)

Ram Expansion Unit images can optionally be loaded via OSD.

Core Loader Sequencing

The core will after power cycle/ cold-boot start downloading the images on the sdcard in the following order:

emulated RAM Expansion Unit REU 1750

For those programs the require a RAM Expansion Unit (REU) it can be activated by OSD on demand.
TN20k supports 512k and 2MByte size whereas Primer, Mega and Console do support also 16MB.

Playing Sonic the Hedgehog V1.2 Enable REU, and load the PRG.
Playing around with GEOS Enable REU, select c1541 CBM DOS ROM and load the PRG.

external IEC device

Use of an external IEC device e.g. C1541 / Printer and support of a selectable D9 Joystick port for hw interfacing is mutually exclusive.

In case MiSTeryShieldRpPico20k J3 spare connector is used for interfacing then a 5V level shifter / open collector driver is needed.
BiDir level shifter like: Converter based on commercial available I2C level shifter PCBA, Transistor circuit or TI TXS104E / TXS108E should be usable.

D9 Joystick port #1
No level shifter is needed as already available on the MiSTeryShield board (for 5V Joystick interfacing).

D9 Port #1

FPGA	TN20k	Signal	D9	any ShieldPico	DualShock	IEC
27	J4‑8	io(0)	6	BTN1	DS2_CLK	CLK (4)
28	J4‑9	io(1)	2	DOWN	DS_MOSI	DATA (5)
25	J4‑10	io(2)	1	UP	DS_MISO	RESET (6)
26	J4‑11	io(3)	4	RIGHT	DS2_CS	ATN (3)
29	J4‑12	io(4)	3	LEFT	–	–
30	J4‑13	io(5)	9	BTN2	–	–
--	J4‑20	GND	8	GND	–	GND (2)
--	J7‑1	5V	7	5V	–	–

D9 Port #2 (or spare header J3 MiSTeryShieldPiPico)
Only MiSTeryShieldRpPico20k-dualD9 port has two D9 ports.

FPGA	TN20k	Signal	D9	ShieldPico dual D9	ShieldPico J3	DualShock	IEC
73	J4‑1	spare(0)	6	BTN1	1	DS2_CLK	CLK (4)
74	J4‑2	spare(1)	2	DOWN	2	DS_MOSI	DATA (5)
77	J4‑5	spare(2)	1	UP	3	DS_MISO	RESET (6)
31	J4‑14	spare(3)	4	RIGHT	4	DS2_CS	ATN (3)
49	J7‑12	spare(4)	3	LEFT	5	–
52	J7‑20	spare(5)	9	BTN2	–	–	–
--	J4‑20	GND	8	GND	6	–	GND (2)
--	J4‑19	3V3	–	–	7	–	–
--	J7‑1	5V	7	5V	8	–	–

Cable side !

Pin	Name	Description
1	/SRQIN	Serial SRQIN
2	GND	Ground
3	ATN	Serial ATN In/Out
4	CLK	Serial CLK In/Out
5	DATA	Serial DATA In/Out
6	/RESET	Reset

Push Button utilization

• S1 open OSD

• S2 Reset

OSD

invoke by F12 keypress

Gamecontrol support

legacy D9 Digital Joystick.

OSD: Retro D9 1 Atari ST type of Joystick 2nd button supported using a MiSTeryNano shield buildin D9 connector.
Don't configure e.g. ArcadeR for C64 mode rather than normal digital 2nd button mode (2nd trigger button connect signal to ground)

OSD: Retro D9 2 Atari ST type of Joystick 2nd button supported using the MiSTeryNano shield spare J8 connector header and extra wiring. ->> wiki
Don't configure e.g. ArcadeR for C64 mode rather than normal digital 2nd button mode (2nd trigger button connect signal to ground)

USB Joystick(s).
OSD: USB #1 Joy or USB #2 Joy Also RII Mini Keyboard i8 left Multimedia Keys are active if USB #1 Joy selected.

Keyboard Numpad.
OSD: Numpad

Numpad		Numpad
0 Trigger	8 Up	. Trigger 2
4 Left	-	6 Right
-	2 Down	-

Mouse.
OSD: Mouse USB Mouse as c1351 Mouse emulation.

USB Paddle.
OSD: USB #1 Padd or USB #2 Padd Left Stick in X / Y analog mode as VC-1312 Paddle emulation. Button cross / square as Trigger

Keyboard

PAGE UP (Tape Play) Key or the Tang S1 Button swap the Joystick Ports if OSD Swap Joys is set to Off mode.

F2,F4,F6,F8,Left/Up keys automatically activate Shift key.
F9 - arrow-up key.
F10 - = key.
F11 (RESTORE) Key as FREEZE. Typically used by Freezer Cards like Action Replay, Snappy Rom etc.
F12 OSD
Alt,Tab - C= key.

LED UI

LED	function	TN20K	TP25K	TM60K	TM138K Pro	Console60K/138k
0	c1541 activity	x	x	x	x	x
1	EZFlash save	x	x	x	x	x

Solid red of the c1541 led after power-up indicates a missing DOS in Flash

Multicolor RGB LED

• green      all fine and ready to go
• red          something wrong with SDcard / default boot image
• blue        MPU firmware detected valid FPGA core
• yellow      FPGA core can't detect valid firmware
• white      -

MIDI-IN and OUT

Type of MIDI interface can be selected from OSD. There is support for Sequential Inc., Passport/Sentech, DATEL/SIEL/JMS/C-LAB and Namesoft. You can use a MiSTeryNano shield to interface to a Keyboard. Note: Enabling persitent the MIDI interface will block other things like Multicard CRT ROMS.

RS232 Serial Interface Swiftlink-232 <-> WIFI Modem

Have a look: Wiki WIFI Modem

Most Terminal programs need the Kernal serial routines therefore select via OSD the CBM Kernal rather than default DolphinDOS.
In addition select OSD System RS232 mode Swiftlink DE. Also possible ACIA 6551 addresses are: $DE00 (default),$DF00 or $D700.

For a PETSCII or ASCII/ANSI BBS you can use ccgms.
Press F8 and select modem Swiftlink DE and Baudrate of 38400.
You can press Shift F8 to toggle in between the different character modes.
Connect to you WIFI AP and have a try: ATD bbs.retrocampus.com:6510 or just have a look at telnetbbsguide and choose as you like.

For a more exotic Turbo56k protocol BBS use retroterm.

Note: Enabling persitent the Swiftlink-232 ACIA 6551 component at $FE00 will block other things like Multicard CRT ROMS. Adress$D700 doesn't block other HW.

RS232 Serial Interface VIC-1011/UP9600 <-> USB-C / external HW pins

The Tang onboard USB-C serial port can be used for communication with the C64 Userport Serial port in VIC-1011 or UP9600 mode. Terminal programs need the Kernal serial routines therefore select via OSD the CBM Kernal rather than default DolphinDOS. For a first start use UP9600 mode and a Terminal program like ccgms and on the PC side Putty with 2400 Baud.

OSD selection allows to change in between TANG USB-C port or external HW pin interface.

Board	RX (I) FPGA	TX (O) FPGA	Note
TN20k	75	76
TP25k	K5	L5	J4-6 J4-5, share M0S Dock PMOD
TM60k NEO	AB20	AA19	J24-6 J24-5, share M0S Dock PMOD
TM138k Pro	H15	H14	J24-6 J24-5, share M0S Dock PMOD

Remember that in + out to be crossed to connect to external device. Level are 3V3 tolerant.

Pinmap D-SUB 9 Joystick Interface

• Joystick interface is 3.3V tolerant. Joystick 5V supply pin has to be left floating !

Joystick pin	IO	Tang Nano pin	FPGA pin	Joystick Function
1	2	J6 10	25	UP
2	1	J6 9	28	DOWN
3	4	J6 12	29	LEFT
4	3	J5 11	26	RIGHT
5	-	-	-	POT Y/ TRIGGER 3
6	0	J5 8	27	TRIGGER
7	-	n.c	n.c	5V
8	-	J5 20	-	GND
9	-	-	30	TRIGGER 2

Getting started

Board Setup