Coder's cable
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The coder's cable is the name given to the serial-based cable some developers use to test and debug code during development. Originally, cables were connected to host devices via serial, but modern cable designs incorporate a USB controller instead. Coder's cables can also be used for other purpose's besides development, such as transferring VMU data back to a PC or dumping GD-ROMs (although quite slowly).
Buy a pre-made cable
- eg: Contact darc on the Message Board or Discord for a pre-made CP2102N-based cable
- eg: retroonyx cable, FTDI-based cable.
- (only mentioned for historical purposes - not sold anymore since long - "Lik-Sang coder's cable" - max speed of 781250)
Build your own cable
- DC serial connector:
- best connector today is the one used by the DC SD Adapter V2 (+- 20 USD)
- select a usb-to-serial chip/cable (+- 15 USD)
- Silicon Labs CP2102N:
- Supports 1600000, which is a 2,4% baudrate mismatch with the Dreamcast, which seems acceptable for high speeds. Best chip that can be recommended today. Tests give speeds of 170-190 kByte/sec and more thanks to compression.
- eg Adafruit CP2102N Friend (USB-C)
- eg Silicon Labs CP2102N-MINIEK (mini USB)
- eg DSD TECH SH-U09BL USB to TTL Serial Cable with CP2102N Chip
- eg Colton's custom PCB - Kicad files to order a custom PCB with a CP2102N, to be soldered to the serial connector of a DC SD Adapter V2
- Silicon Labs CP2102N:
- FDTI's FT232R-like chips:
- good until 781250, does not support 1562500.
- 500000 and 1500000 will not work with all chips/on all pc, because of a 4% baud rate mismatch with the baudrates of the Dreamcast.
- Even if you're lucky, you won't really get 1500000-worthy speeds - more probably around 130-150 kByte/sec...
- FDTI's FT232R-like chips:
- connect the following pins (cfr Serial_interface):
- GND <-> GND
- TXD <-> RXD
- RXD <-> TXD
- RTS <-> CTS
- CTS <-> RTS
Software to use
Supported Baud Rates
Not all common baudrates work, so the recommendations are:
- up until 115200, you can use the common baudrates: 9600, 19200, 38400, 57600, 115200
- if 115200 does not work, you can add the "-e" speedhack option
- higher baudrates:
- try first with the dreamcast-specific baudrates (223214, 260416, 312500, 390625, 520833, 781250, 1562500)
- Disclaimer for Linux only: needs dc-tool-ser (host) changes from 4 september 2023 to select custom baudrates
- Disclaimer for MacOS only: custom baudrates are not supported yet
- 230400: use the -e speedhack option if you absolutely need 230400 at pc-side, but the DC will use 223214 or 260416 anyways.
- 500000 and 1500000: you can try, but that will not work on all pc (the mismatch with the baudrate of the Dreamcast is sometimes too big (4%))
- try first with the dreamcast-specific baudrates (223214, 260416, 312500, 390625, 520833, 781250, 1562500)
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