Datasheet

DocID012578 Rev 16 41/64

M41T82, M41T83 Clock operation

3.9 Square wave output (M41T83 only)

The M41T83 offers the user a programmable square wave function which is output on the

SQW pin. RS3-RS0 bits located in 13h establish the square wave output frequency. These

frequencies are listed in Table 13. Once the selection of the SQW frequency has been

completed, the SQW pin can be turned on and off under software control with the square

wave enable bit (SQWE) located in register 0Ah.

Note: If the SQWE bit is set to '1' and V

falls below the switchover (V

) voltage, the square

wave output will be disabled.

Table 13. Square wave output frequency

Square wave bits Square wave

RS3 RS2 RS1 RS0 Frequency Units

0 0 0 0 None –

0 0 0 1 32.768 kHz

0 0 1 0 8.192 kHz

0 0 1 1 4.096 kHz

0 1 0 0 2.048 kHz

0 1 0 1 1.024 kHz

0 1 1 0 512 Hz

0 1 1 1 256 Hz

1 0 0 0 128 Hz

1 0 0 1 64 Hz

1 0 1 0 32 Hz

1 0 1 1 16 Hz

11008Hz

11014Hz

11102Hz

11111Hz