Specifications

HM-BT4502 V1.0
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Note: This parameter is not saved on power failure, and RTC needs to be set
again when the module is powered on again.
9.15 Data Delay Setting
Input the string "TTM: CDL-Xms" to the serial port RX and set the delay
between the INT setting and the TX output. The unit is ms.
Among them, X= "0", "2", "5", "10", "15", "20", "25". If the instruction is correct,
the confirmation string "TTM: OK\r\n\0" will be received from TX. If the
instruction format is incorrect, the "TTM: ERP\r\n\0" will be received.
In order to have enough time to wake up the MCU from the sleep status, the
module provides the delay (X) setting. The module sets the INT to the low level
before the serial port TX outputs the data. The delay between the INT setting
and the TX output is decided by this parameter. The minimum delay is not less
than X. The actual delay is T = ( X + Y ) ms, of which 500us < Y < 1ms. This
parameter is saved on power failure.
9.16 Battery Level Setting
The module has no ADC voltage sampling; it needs the MCU to provide the
battery voltage. The MCU sends the string "TTM: BST-Xrn0" from serial port,
where X is the percentage of the remaining capacity in decimal system. If the
data is sent correctly, the module returns the string "TTM: OK\r\n\0" through
the serial port. If the data is sent incorrectly, the module returns the string