FX2 - an attempt with USB 2.0

A PCB (160 mm x 100 mm) for experimenting with the Cypress EZ-USB FX2 USB 2.0 Chip

This IC contains a complete USB 2.0 interface with 480 Mbit/s throughput, a comfortable FIFO with a controller (state machine), but is hard to use due to its very small housing and pitch.
This chip, CY7C68013-128 TQFP, is used to have an option for external memory. Mostly, for debugging.

This PCB is only two-sided and hand-madeable vias, therefore, any hobbyist with UV lamp and etching fluid can make this.

Possible uses of this board are:

File list:


…was made in Eagle according to the Cypress reference design CY3681. Due to lack of FPGA/CPLD (??) there are no LEDs, but that's the only disadvantage I have found.
RAM, ATA connector, RS232, and port expander PCF8574 are compatible. All FX2 signals are available on an ERNI connector for 19" racks.
For the scope probe, an A/D converter is spared.
Schematic ICs Schematic Connectors
Schematic sheets
Please click onto images to view the schematics! Last change: The LM317LZ was not sufficient as linear regulator; instead, a simple solution with zener diode and transistor is used.

PCB layout

...you should bring it to work step by step.
PCB, top side PCB, bottom side
Partial placed components
You can place both 1206 and 0805 shaped SMD resistors and capacitors.
IC CY7C68013-128AC = EZUSB FX2
Detail view: hand-soldered 128 pin chip

Building up

First placement

Please populate step by step and test the board! No more!


Plug this card on your PC. If it reports an error, check the following: Then you give the Windows popup dialog the EZUSBW2K.INF from Cypress development kit. Then start EzMr.exe and check if the device is found.

Recognition of high-speed mode is possible by inspecting pipe sizes of more than 64 Bytes for bulk transfer.

More components

You may now populate the PCB. I advise to place the IDE connector and some R/C and LED "DASP" (Drive Active / Slave Present) around to check connection to a hard disk.

Check it using following procedure:

The firmware is active to the USB side ONLY if it detects a hard disk!! The HDD LED (»DASP«) must light on shortly, then you get an USB hard drive. In Windows 98 you need another driver:
Board with IDE hard disk
Connection with IDE hard drive(It works!)


When you program the EEPROM, and your system crashes meanwhile, you may result in a crashing 8051 firmware. Then, you cannot start the board with plugged jumper, and for accessing the EEPROM with EzMr.EXE, you need a 2-byte-adressed EEPROM on FX2 startup! (Bit ID1 in I2CS @0xE678 set). How you can delete at least the first Byte of EEPROM without pulling the chip out and into an external programmer? The right way:

Size comparison

Unfortunalely, all FX2 chips are about same in size:
Size comparison of packages on 5 mm grid paper

See also