Bidirectional CS Line for Interrupt Management
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing digital communication interfaces, such as SPI and I2C, face challenges in efficient interrupt management due to the need for additional dedicated pins and wires, leading to area occupation and routing issues, especially in systems with multiple connected devices, and bandwidth congestion when using in-band interrupt methods.
Innovation Solution
The proposed solution utilizes a bidirectional CS line for both slave-device selection and interrupt requests, eliminating the need for additional interrupt lines and allowing multiple devices to send interrupts simultaneously without bus contention, by using the existing CS line for bidirectional communication between the master and slave devices.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If dedicated interrupt lines are added for each slave device, then interrupt management capability is improved, but the number of pins and wires increases leading to area occupation and routing issues
Solution Approach 1:
The CS (Chip Select) line is made bidirectional to serve dual purposes: unidirectionally selecting slave devices from master to slave, and bidirectionally transmitting interrupt requests from slave to master. This multi-functionality eliminates the need for separate dedicated interrupt lines, reducing pin count while maintaining full interrupt management capability for multiple slave devices
Solution Approach 2:
The patent combines the slave selection function and interrupt request transmission function into a single bidirectional CS line. By merging these two previously separate functions into one communication channel, the system reduces wiring complexity and area occupation while preserving reliable interrupt management across multiple slave devices
2Device complexity
If in-band interrupt method is used to share data communication lines, then bandwidth requirements are reduced, but bandwidth congestion and delayed interrupt requests occur
Solution Approach 1:
The patent segments the communication functions by dedicating separate unidirectional CS lines to each slave device while making them bidirectional for interrupt requests. This segmentation allows simultaneous interrupt transmission from multiple slaves without contention, avoiding the bandwidth congestion that occurs when all devices share a single in-band interrupt channel
3Adaptability or versatility
If multiple slave devices are connected to the same bus, then system integration is improved, but area occupation and routing complexity increase
Solution Approach 1:
Each slave device uses its dedicated bidirectional CS line for both selection and interrupt requests, making the line multi-functional. This approach supports scalable system integration with multiple slave devices while maintaining constant wiring per device, preventing area occupation and routing complexity from increasing linearly with the number of devices
Data Source
AI summary
In a digital communication system, a master device and a number of slave devices are coupled in communication with the master device over a shared data communication bus. A selection line for each one of the slave devices couples the master device with a respective slave device and is dedicated to selection by the master device of the respective slave device for communication over the shared data communication bus. Each of the slave devices is able to send an interrupt request to the master device over the respective selection line to be served by the master device initiating a communication over the shared data communication bus, each selection line thereby being a bidirectional communication line between the respective slave device and the master device.