FingerTIP
Infineon Technologies
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FTF 1100 MF1 V2.0 databook 3.3 (05.00)
Once the sensor has completed its power-on reset (see table 7), first the dynamics must
be set with the Set Mode command. The Set Mode command must be sent before every
image readout. Next, the pixel pointer must be reset to position (1,1) with the Reset
Pointer command. Then the status byte is read out until the image data is. This is done
with the Read Status command. A timeout condition should be used for this test loop. It is
recommended to stop after 100 loops.
Now the image data can be read out. The Read Data command starts the readout. After
sending the Read Data command, the first byte output by the sensor is the command
response. The next bytes are the image data. 225 SPI byte read cycles are needed for
reading a complete line. The 225
th byte of each line is the LineEndMark and must be 00h.
Sometimes, interference such as ESD air discharge and alike can force double clocking on
the sensor and the LineEndMark may not be 00h. Usually this kind of interference is
singular and temporary. Therefore it is recommended to start reading a new image. After
64800 (225 x 288) SPI byte read cycles the whole image is read out.
If more than three readouts have failed because of LineEndMark error, the read out should
be stopped in order to analyze the error. For more information and error handling please
see the Design-In Guideline /2/.
Once the image readout is finished and the sensor is not needed for the moment, the
sensor should be set to sleep mode.
4.6 Pinout of the FingerTIP in SPI Mode
In figure 17, the pinout of the FingerTIP module is shown. Table 12 shows the pin
names and the pin direction, including a short description.
Some of the pins are multi-function pins, depending on the selected interface mode – EPP
or SPI. Chapter 5 gives a complete overview of the pins for EPP and SPI mode. The pad
characteristics are also shown in chapter 5.
Figure 17: Pinout of the FingerTIP Sensor Module
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Module