1. Increasing Power Meter Transfer Rates Using a FT2232H Interface Chip
Ernest Yim, William Li, Samuel Gunaseelan

2. Introduction “Make it faster” Possibilities Optimize code
Change microcontroller
PIC32 *
ATSAM3U4E
Cypress EZ-USB FX2
Use Ethernet
Hi-Speed vs. Full Speed

3. Power Meter Reads power data Calibration needed
Has two PIC24 microcontrollers
Guides written (fusdisk\powermeter)
Two channels
Full speed
Fig. 1 – Power Meter

4. The Interface Chip FTDI’s FT2232H Cost effective
Mini-module (dev board): $27.00
FT2232H: $6.70
Hi-speed support
12MHz clock (480Mhz w/ PLL)
2 Channels
Fig. 2 – FT2232H

5. Console Application
Fig. 3 – Console application written to receive data on computer side

6. The Setup: Asynchronous Bit-Bang Mode
Fig. 6-8 – power meter’s ADC (forward) output connected to ft2232h mini module for asynchronous bit-bang mode (connected to computer via USB)

7. Asynchronous Bit-Bang Mode
6-8Mbaud rate
4.8Mbaud (experimental max.)
Sample rate: ~83.33ns
150% increase in speed
Tested by sending square waves into pins
Raw power data can be converted

8. The Setup: Fast Opto-Isolated Serial Mode
Fig – power meter’s ADC (forward) output connected to ft2232h mini module for fast opto-isolated serial interface mode (connected to computer via USB)

9. Fast Opto-Isolated Serial Interface Mode
Transfer speed depends on external clock
No limit?
Translation of bits needed
Bit-shift register (PISO)
Little success with translation

10. Conversion: No pattern
Fig. 12 – Screenshot of serial data (binary), no apparent pattern can be found to translate data, but ADC values seem to be in data

11. Verdict Asynchronous Bit-Bang Mode Works
Power data matches data of current powermeter
150% increase
Fast Opto-Isolated Serial Interface Mode
Proper conversion needed
Possible potential for greater speeds
Side Projects
Test notch, band-pass, band-reject filter designs
Test and calibrate power meters
Matching circuit

12. Acknowledgements I would like to thank everyone in the C7 Lab
And especially,
Dr. Kullervo Hynynen
Vivian Sin
William Li
Samuel Gunaseelan