JAJSLF6I October 2005 – June 2022 PCA9546A
PRODUCTION DATA
One or several SCn/SDn downstream pairs, or channels, are selected by the contents of the control register (see Table 8-1). This register is written after the PCA9546A has been addressed. The four LSBs of the control byte are used to determine which channel or channels are to be selected. When a channel is selected, the channel becomes active after a stop condition has been placed on the I2C bus. This ensures that all SCn/SDn lines are in a high state when the channel is made active, so that no false conditions are generated at the time of connection. A stop condition always must occur right after the acknowledge cycle.
B7 | B6 | B5 | B4 | B3 | B2 | B1 | B0 | COMMAND |
---|---|---|---|---|---|---|---|---|
X | X | X | X | X | X | X | 0 | Channel 0 disabled |
1 | Channel 0 enabled | |||||||
X | X | X | X | X | X | 0 | X | Channel 1 disabled |
1 | Channel 1 enabled | |||||||
X | X | X | X | X | 0 | X | X | Channel 2 disabled |
1 | Channel 2 enabled | |||||||
X | X | X | X | 0 | X | X | X | Channel 3 disabled |
1 | Channel 3 enabled | |||||||
0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | No channel selected, power-up/reset default state |