5.6.3 Inter-Integrated Circuit (I2C)
AVR Two-Wire Interface (TWI) and PIC32CM Serial Communication (SERCOM) provide Philips I2C-compatible peripherals for flexible inter-device communication on a shared bus. Both peripherals support Host and Client modes, standard and fast I2C speeds (up to 1 MHz), multi-host arbitration, and bus error detection. Table 5-23 shows a comparison of features between AVR and PIC32CM.
| Feature/Variant | AVR® TWI | PIC32CM I2C (SERCOM) |
|---|---|---|
| Integration | Stand-alone TWI peripheral | Mode in SERCOM (Serial Communications) peripheral |
| Host/Client Modes | Supported | Supported |
| Addressing |
7-bit General call Address masking Dual address match |
7-bit, 10-bit General call Address masking Dual address match |
| Data Buffering | Shift register | 16-byte internal FIFO |
| DMA Support | N/A | Supported |
| Bus Speeds Supported | 100 kHz, 400 kHz, 1 MHz | 100 kHz, 400 kHz, 1 MHz |
| SMBus/PMBus™ Support | SMBus 2.0 compatible | SMBus and PMBus compatible |
| Multi-Host Arbitration | Supported | Supported |
| Wake-up from Sleep | Supported (on address match) | Supported (on address match) |
| Input Filtering | Noise suppression | Filtered inputs, slew-rate limited outputs |
| 4-Wire Operation | No | Yes (for advanced protocols) |
| Data Extension | No | 32-bit data extension |
| FIFO | No | 16-byte FIFO |