sx8644 Semtech Corporation, sx8644 Datasheet - Page 72

• Manufacturer Part Number: sx8644
• Description: Ultra Low Power, Capacitive Button And Slider Touch Controller 12 Sensors With Enhanced Led Drivers
• Manufacturer: Semtech Corporation

ADVANCED COMMUNICATIONS & SENSING
6.6.2
The SPM read can be done in any mode (Active, Doze, Sleep).
The SPM must always be read in blocks of 8 bytes. The sequence is described below:
The complete SPM can be read by repeating 16 times the cycles shown in Figure 55 using base addresses 0x00,
0x08, 0x10, …, 0x70, 0x78.
Revision 7_3, January 10
1. Set the I2C in SPM mode by writing “01” to SpmCfg[5:4] and SPM read access by writing ‘1’ to SpmCfg[3].
2. Write the SPM base address to SpmBaseAddr (The base address needs to be a value modulo 8).
3. Read the eight consecutive bytes from I2C address 0, 1, 2, …7
4. Terminate by writing “000” to SpmCfg[5:3].
SPM Read Sequence
Figure 55: SPM Read Sequence
Touch Controller (12 sensors) with Enhanced LED Drivers
© 2009 Semtech Corp.
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Ultra Low Power, Capacitive Button and Slider
DATASHEET
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SX8644