27.5.14 Slave Address Mask

Name: SADDRMASK
Offset: 0x0E
Reset: 0x00
Property: -

Bit 76543210 
 ADDRMASK[6:0]ADDREN 
Access R/WR/WR/WR/WR/WR/WR/WR/W 
Reset 00000000 

Bits 7:1 – ADDRMASK[6:0] Address Mask

The ADDRMASK register acts as a second address match register, or an address mask register depending on the ADDREN setting.

If ADDREN is written to '0', ADDRMASK can be loaded with a 7-bit Slave Address mask. Each of the bits in the TWIn.SADDRMASK register can mask (disable) the corresponding address bits in the TWI slave Address Register (TWIn.SADDR). If the mask bit is written to '1' then the address match logic ignores the compare between the incoming address bit and the corresponding bit in slave TWIn.SADDR register. In other words, masked bits will always match.

If ADDREN is written to '1', the TWIn.SADDRMASK can be loaded with a second slave address in addition to the TWIn.SADDR register. In this mode, the slave will match on two unique addresses, one in TWIn.SADDR and the other in TWIn.SADDRMASK.

Bit 0 – ADDREN Address Mask Enable

If this bit is written to '1', the slave address match logic responds to the two unique addresses in slave TWIn.SADDR and TWIn.SADDRMASK.

If this bit is '0', the TWIn.SADDRMASK register acts as a mask to the TWIn.SADDR register.