3.2 Upgraded System using the Multi-Protocol Translator

Figure 3-2 demonstrates a multi-protocol translator that can help overcome the drawbacks of the mixed bus design. A microcontroller with I3C Target capability is added to the system, which acts as a Protocol Translator. The host device is an I3C-capable Controller, which needs to support only the I3C communication. The protocol translator with I3C Target capability, I²C, SPI and UART interfaces works as an I3C to the serial converter. It acts as a bridge device and isolates the I²C /SPI/UART-based devices from the I3C Controller. This allows the I3C Controller to maintain a pure I3C bus and communicate with the devices interfaced over other protocols through the multi-protocol translator.

Since the host device requires only a pure I3C bus, the overall complexity of bus management and software handling for the I3C Controller is reduced compared to a device handling different communication interfaces. The I3C Target module of the multi-protocol translator uses the In-Band Interrupt (IBI) feature to relay all the interrupts from the I²C /SPI client devices to the I3C Controller without using extra pins on the Controller side. The I3C Controller can use the Target Reset Pattern feature to reset the client devices. The Controller uses only SCL and SDA lines to send reset patterns, eliminating the need for additional pins. Thus, the system needs only two pins i.e., the SCL and SDA lines on the host side.