FAQ's S Last changes: 07.05.2007 - Glyn High-Tech Distribution

Q: Do the UACB supports Mac OS
A: Since MAC OS 10.xx the UACB will work with Mac OS. We do not guaranty that the
UACB will also work with Mac OS 9.xx.
FAQ’s
Q: I see that the UACB has 12 GPIO Pins how I can get access over USB from a Windows
application
A: You will find sample code in our service area under:
UAC35xxB > Software > Code samples > Windows
Q: Which of the 12 GPIO pins are used by the internal firmware
A: Codec Firmware:
GPIO 0 = Main output Vol. up
GPIO 1 = Main output Vol. down
GPIO 2 = Main output Mute toggle
GPIO 3 = Bass-Boost
GPIO 4 = Mic Mute (not visible on windows side).
GPIO 10 = High at start-up = No HID => all GPIO inputs above without function!
Headset Firmware:
GPIO 0 = Main output Vol. up
GPIO 1 = Main output Vol. down
GPIO 2 = Main output Mute On-off toggle
GPIO 3 = Bass-Boost
GPIO 4 = Mic Mute (not visible on windows side).
GPIO 5 = High at start-up = No HID => all GPIO inputs above without function!
Q: How can I switch off the HID functionality (e.g. Vol. up/down, Mute) via GPIO’s
because I need the GPIO’s for something else
A: Connect GPIO 10 to DVDD (high) before you power up (USB enumeration) the device.
After USB enumeration you can remove the connection to GPIO 10. No HID descriptor
will be loaded.
UAC3556B G6 (codec ROM firmware) not working like described above.
UAC3556B G7 (codec ROM firmware) is working like described above.
UAC3576B H7 (codec ROM firmware) is working like described above.
Q: I'm reading I2C data from the bus and bridge it via UACB and USB to my Windows
application. I increased the I2C bus speed from 100KHz to 400KHz but see no speedup.
A: the I2C limitations are on the USB bus. Because our device will only support full
speed there are the following limitations:
Internal we communicate via Vendor specific requests (I2C) to pipe 0 with a FIFO
size of max 64Byte. This means in max you can
read/write one I2C package of max. 64Byte in 1ms on a UHCI controller (512KBit/s)
or
read/write 13 I2C package of max. 64Byte in 1ms on an OHCI controller (6.6MBit/s).
Because most I2C commands will only have some bytes you will never reach the
400KHz clock speed via USB.
The only quick solution is to use an OHCI to speed up your I2C read/write.
In no event shall Micronas be liable for indirect, incidental, consequential, punitive, special or other damages whatsoever including without limitation,
damages for loss of business profits, business interruption, loss of business information, and the like, arising out of or relating to the use of or the
inability to use the Application
Note, even if Micronas has been advised of the possibility of such damages, except personal injury or death resulting from Micronas’ negligence.
G
S Last changes: 07.05.2007