Universal USB Serial Port
- Supports software, hardware, or no handshaking (TXD, RXD, RTS#, CTS#)
- TXD and RXD status LEDs show traffic at a glance
- Connects to PC via full speed USB or RS232
- Uses industry standard FTDI FT230, requires no driver on Linux, also has Virtual Com Port (VCP) drivers for Windows and OSX available from FTDI
- Android FTDI UART Terminal app available free on
Google Play
or download
directly
(User Manual and source code are also available.) - Interface PC to 5V serial on Arduino AVRs and other microcontrollers
- Interface PC to 3.3V serial on Raspberry Pi, Arduino Due, STM32F4 Discovery, ARMs, 3.3V PICs, ...
USB Serial Port Block diagram
(click for bigger version)
Level Shifters
Two banks of jumper programmable six channel level shifters (74VHCT50s)
- Jumper 2 controls the left shifter on J14
- Jumper 3 controls the right level shifter on J15
To configure the level shifter
- Up translate voltages from 3.3V to 5V (set Jumper to the UP position)
- Down translate voltages from 5V to 3.3V (set Jumper to the DOWN position)
Debug LEDs
- 8 LEDs which light when driven via header J1 with 3.3V or 5V.
- LEDs only draw 5mA @ 5V (can be driven directly by most common microcontroller and IC output pins)
Clocks
The master clock signal originates from the CBUS0 pin on the FTDI 230. When shipped, this pin is configured to generate a 24Mhz square wave. CBUS0 can also be reconfigured to generate 12Mhz or 6Mhz if desired, using the FT_PROG Windows program available from FTDI.
These clock signals are available on J13's pins:
| 1 | 2 | 3 | 4 | 5 | 6 | 7 |
| 24Mhz | 12Mhz | 1.5Mhz | 750Khz | 375Khz | 187.5Khz | 93.8Khz |
| 12Mhz | 6Mhz | 750Khz | 375Khz | 187.5Khz | 93.8Khz | 46.9Khz |
| 6Mhz | 3Mhz | 375Khz | 187.5Khz | 93.8Khz | 46.9Khz | 23.4Khz |
| 8 | 9 | 10 | 11 | 12 | 13 | 14 |
| 46.9Khz | 23.4Khz | 11.7Khz | 5.9Khz | 2.9Khz | 1.5Khz | GND |
| 23.4Khz | 11.7Khz | 5.9Khz | 2.9Khz | 1.5Khz | 732Hz | GND |
| 11.7Khz | 5.9Khz | 2.9Khz | 1.5Khz | 732Hz | 366Hz | GND |
Note: clocks are derived from the USB signal, so they are only available when USB is connected.
Power
Powered by USB or external 5V supply