26.5.14 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 ADDRMASK register can mask (disable) the corresponding address bits in the TWI slave Address Register (ADDR). 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 ADDR register. In other words, masked bits will always match.

If ADDREN is written to '1', the slave ADDRMASK can be loaded with a second slave address in addition to the ADDR register. In this mode, the slave will match on 2 unique addresses, one in ADDR and the other in ADDRMASK.

Bit 0 – ADDREN Address Mask Enable

If this bit is written to '1', the slave address match logic responds to the 2 unique addresses in slave ADDR and ADDRMASK.

If this bit is '0', the ADDRMASK register acts as a mask to the slave ADDR register.