Control A
Bit7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
SDASETUP | SDAHOLD[1:0] | FMPEN | |||||
Access | R/W | R/W | R/W | R/W | |||
Reset | 0 | 0 | 0 | 0 |
SDA Setup Time
By default, there are 4 clock cycles of setup time on SDA out signal while reading from slave part of the TWI module. Writing this bit to '1' will change the setup time to 8 clocks.
Value | Name | Description |
---|---|---|
0 | 4CYC | SDA setup time is 4 clock cycles |
1 | 8CYC | SDA setup time is 8 clock cycle |
SDA Hold Time
Writing these bits selects the SDA hold time.
SDAHOLD[1:0] | Nominal Hold Time | Hold Time Range across All Corners (ns) | Description |
---|---|---|---|
0x0 | OFF | 0 | Hold time off. |
0x1 | 50ns | 36 - 131 | Backward compatible setting. |
0x2 | 300ns | 180 - 630 | Meets SMBus specification under typical conditions. |
0x3 | 500ns | 300 - 1050 | Meets SMBus specification across all corners. |
FM Plus Enable
Writing these bits selects the 1MHz bus speed (Fast mode plus, Fm+) for the TWI in default configuration.
Value | Description |
---|---|
0 | Fm+ disabled |
1 | Fm+ enabled |