19.3 Client Address Masking
The I2CxMSK register (I2CxMASK)
designates address bit positions as “don’t care” for both 7-Bit and 10-Bit Addressing
modes. Setting a particular bit location (= 1
) in the I2CxMSK register
causes the Client module to respond, whether the corresponding address bit value is a
‘0
’ or a ‘1
’. For example, when I2CxMSK is set to
‘0010000000
’, the Client module will detect both addresses,
‘0000000000
’ and ‘0010000000
’.
To enable address masking, the Intelligent Peripheral Management Interface (IPMI) must be disabled by clearing the STRICT bit (I2CxCONL[11]).
Note: As a result of changes in the I2C protocol, the addresses in Table 19-2 are
reserved and will not be Acknowledged in Client mode. This includes any address mask
settings that include any of these addresses.
FCY | FSCL | I2CxBRG Value | |
---|---|---|---|
Decimal | Hexadecimal | ||
100 MHz | 1 MHz | 41 | 29 |
100 MHz | 400 kHz | 116 | 74 |
100 MHz | 100 kHz | 491 | 1EB |
80 MHz | 1 MHz | 32 | 20 |
80 MHz | 400 kHz | 92 | 5C |
80 MHz | 100 kHz | 392 | 188 |
60 MHz | 1 MHz | 24 | 18 |
60 MHz | 400 kHz | 69 | 45 |
60 MHz | 100 kHz | 294 | 126 |
40 MHz | 1 MHz | 15 | 0F |
40 MHz | 400 kHz | 45 | 2D |
40 MHz | 100 kHz | 195 | C3 |
20 MHz | 1 MHz | 7 | 7 |
20 MHz | 400 kHz | 22 | 16 |
20 MHz | 100 kHz | 97 | 61 |
Note:
|
Client Address | R/W Bit | Description |
---|---|---|
0000 000 | 0 | General Call Address(2) |
0000 000 | 1 | Start Byte |
0000 001 | x | Cbus Address |
0000 01x | x | Reserved |
0000 1xx | x | HS Mode Host Code |
1111 0xx | x | 10-Bit Client Upper Byte(3) |
1111 1xx | x | Reserved |
Note:
|