being transferred and when data is being transferred at the maximum rate possible.
The operating mode can best be described by stating the AT commands required to enter that mode. In addition, there are certain S Registers which have a direct impact on power consumption, which are described next.
The blu2i Module has 2 LEDs which can be configured to display connection status. One led is used to display connection status, while the other is used to either display ‘Ring Indicate’ status or follow the state of the incoming DSR line on the UART interface. Tests have shown that these LEDs can consume up to 5.3mA which is more than double the current draw when in Idle mode. Therefore S Registers 533 and 534 can be used to completely disable these indications.
Finally S Registers 508 to 511, which specify the page and inquiry scan intervals and windows, can be used to adjust the average current drain when in discoverable and or connectable modes. Registers 508 and 509 specify the interval and window for page scans and registers 510 and 511 specify the interval and window for inquiry scans. Register pairs 508/509 and 510/511 describe duty cycles when the blu2i module goes into scan modes. It is while scanning that the highest current draw occurs. The average current draw is determined by simple arithmetic using the values stored in the 508/509 and 510/511 register pairs.
The operating modes described above are entered using AT commands as follows
Idle | On power up, with S Register 512 = 1 |
Wait for Connection | AT+BTG (100% page scan duty cycle) |
Discoverable Only | AT+BTQ (100% inquiry scan duty cycle) |
Connecting | ATD |
Connected | No Data |
Connected | Max data transfer |
All current consumption values in the table below assume that the connection status indication functionality of the LEDs has been disabled by setting S Registers 533 and 534 to 0.
All current values are in milliamps (mA).
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