(My customer support ticketed asked that I post to the form to get answers.)
We are planning on having 4 DRV2605YZFR parts on the same I2C bus.
Our plan is to wire the EN pins of each Haptic Driver to separate GPIOs of the MCU.
However, the data sheet has two notes:
Note 1: This seems possible based on the data sheet paragraph...
7.5.3.1 TI Haptic Broadcast Mode The DRV2605 device features the TI haptic broadcast mode where the DRV2605 responds to the slave address 0x58 (7-bit) or 1011000. Haptic broadcast mode is useful in the event that multiple drivers implementing the TI haptic broadcast mode are installed in the system. In such a scenario, writing the GO bit to the TI haptic broadcast slave address will cause all haptic drivers to trigger the process at the same time.
Can you give details on how this should be implemented?
Note 2: When the haptic driver is deactivated (EN pin low) it will still ACK I2C transactions.
7.4.1.3 Operation With EN Control The EN pin of the DRV2605 device gates the active operation. When the EN pin is logic high, the DRV2605 device is active. When the EN pin is logic low, the device enters the shutdown state, which is the lowest power state of the device. The device registers are not reset. The EN pin operation is particularly useful for constantsource PWM and analog input modes to maintain compatibility with non-I2C device signaling. The EN pin must be high to write I 2C device registers. However, if the EN pin is low the DRV2605 device can still acknowledge (ACK) during an I 2C transaction, however, no read or write is possible. To completely reset the device to the powerup state, set the DEV_RESET bit in register 0x01.
This means that even with the EN pin low to a Haptic Driver it will still ACK I2C transactions. Thus, at the I2C ACK/NACK period there will be multiple devices driving the bus at the same time.
Are there details I should know about this?
