![]() While the FT232BL runs at 5volts from the USB supply, its serial IO pins have an independent supply input – they can operate at another voltage. The FT232BL RXLED pin sinks current, so we powered the LED from the 5volt USB supply through a 1.1K resistor (R3). A single LED (LED4/USB) indicates USB status and activity. C4 is a decoupling capacitor for the FTDI232BL supply pin. The FT232BL is powered directly from the filtered, unregulated USB supply. We had no problem hand-soldering it to a professional PCB, but it’s not for everyone. This is the latest generation chip, and it’s only available in small SSOP and QFN packages. ![]() FTDI has extensive driver support for most platforms, we used the virtual com port drivers. You might be familiar with this chip from various Arduino boards. We used this one, which is rated for 1500ma and costs 10 cents.Īn FTDI FT232BL USB->serial chip (IC2) handles the USB connection. Use a ferrite bead rated for at least 1000ma to be safe. We can guestimate that the Bus Pirate’s worst case current consumption is 525ma (3 power supplies 150ma, the FTDI chip 25ma, 2 LEDs 50ma max). Its purpose is to filter small power fluctuations, all the current for the circuit will go through it. We used the small, still-not-quite-common, USB mini-b connector (J2).Ĭhoosing a ferrite bead is a common hangup. The Bus Pirate is powered from the USB 5volt supply, which is first filtered with a ferrite bead (L1) and 10uF tantalum capacitor (C21). The programming pins are brought to a five pin header (ICSP) on the edge of the PCB. The internal 2.5volt regulator requires a 10uF tantalum capacitor (C20). Each PIC power pin gets a 0.1uF bypass capacitor (C1,2). The PIC (IC1) is powered by a 3.3volt regulator (VR2, C23). It’s cheap, has a ton of memory, a couple 5volt tolerant input pins, and the peripheral pin select feature lets us assign hardware modules anywhere we want. V2 uses the same 24FJ64GA002 as the previous Bus Pirate versions. Download the latest files from our Google Code page.Ī Microchip PIC24F series microcontroller generates the user interface and translates input into bus communications. The schematic and board layout were made with the freeware version of Cadsoft Eagle. More protocols are being added all the time, check out the source code on our Google Code SVN page.Ĭlick for a large image of the schematic (PNG). Bit-wise 2- and 3-wire libraries can interface most proprietary serial protocols. The latest firmware supports 1-Wire, I2C, SPI, JTAG, asynchronous serial, MIDI, and PC keyboards. See our Bus Pirate page for full documentation. Commands are translated to the bus protocols that control microchips. The user send commands to the Bus Pirate from a serial terminal on the PC. The Bus Pirate connects to a PC USB port. Read about the new design after the break. If you want to get your hands on some Bus Pirate USB goodness, Seeed Studio has assembled hardware for $30 (including worldwide shipping). We also reduced the part count and cost wherever possible. The new v2 family adds USB power and connectivity to the best Bus Pirate design yet. We added some other features we frequently need, like pulse-width modulation, frequency measurement, voltage measurement, bus sniffers, pull-up resistors, and switchable 3.3volt and 5volt power supplies. It currently supports most serial protocols, including 1-Wire, I2C, SPI, JTAG, asynchronous serial, MIDI, and more. The Bus Pirate is a universal serial interface tool, we use it to test new chips without writing any code. Update, Saturday July 4th, 2009: All preorders are closed.
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