STV0681
Customising the STV0681
5
Customising the STV0681
The firmware inside the STV0681 is stored in ROM and may not be changed. It is possible,
however, to use an external serial EEPROM to store certain information to allow a degree of
customization of the device.
The STV0681 reports a USB Vendor ID (VID) of 0553(hex) and a Product ID (PID) of 0202 (hex).
Alternative values for the VID and PID as well as Manufacturer and Product strings may be stored in
an external EEPROM.
In addition to USB descriptor information, the EEPROM may also be used to set various other
parameters as follows:
● Auto power-down time: this is the length of time before the STV0681 shuts down after no activity.
● Mode button power-down time: the length of time you must hold the Mode button to powerdown the
system.
● 50Hz/60Hz flicker-free selection: the EEPROM allows this selection to be via a GPIO pin on the
STV0681 or fixed at either 50Hz or 60Hz
● Number of self-timer beeps
5.1
External EEPROM
An external 128byte serial EEPROM may be used in conjunction with STV0681 to hold customer
specific information.
The EEPROM is connected onto the sensor IIC bus and must be set to IIC address A0 (hex). The
EEPROM is auto-detected by the STV0681 and no additional changes need to be made. A suitable
EEPROM device is manufactured by STMicroelectronics part number M24C01W (alternatives are
available from other suppliers).
ADCS 7283313C
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STMICROELECTRONICS [ ST ]
