Method and system for interrupt signaling in an inter-integrated circuit (I2C) bus system
AssigneeNXP B.V.
InventorsDavid Alan Du, Anubhav Gupta, Peter James Stonard
Life of this patent
Estimating the term…
Abstract
Embodiments of a method and system are disclosed. One embodiment of a method for signaling an interrupt in an I2C system that includes a master I2C device and at least one slave I2C device that are connected by an SDA line and an SCL line is disclosed. The method involves, at the slave I2C device, pulling the SDA line low to signal an interrupt and at the slave I2C device, releasing the SDA line in response to either the SCL line having been pulled low or the expiration of a predetermined time period, whichever occurs first. In an embodiment, the predetermined time period is 1 ms.
Claims14
A method for signaling an interrupt in an I2C system that includes a master I2C device and at least one slave I2C device that are connected by an SDA line and an SCL line, the method comprising:
- at the at least one slave I2C device, pulling the SDA line low to signal an interrupt;
- at the master I2C device, after the at least one slave I2C device pulled the SDA line low to signal the interrupt, pulling the SCL line low to complete a START and then emitting an address request command to the at least one slave I2C device;
- and
- at the at least one slave I2C device, responding to the address request command by sending an I2C address of the at least one slave I2C device to the master I2C device.
A method for signaling an interrupt in an I2C system that includes a master I2C device and at least one slave I2C device that are connected by an SDA line and an SCL line, the method comprising:
- at the at least one slave I2C device, pulling the SDA line low to signal the interrupt;
- at the master I2C device, after the at least one slave I2C device pulled the SDA line low to signal the interrupt, pulling the SCL line low to complete a START and then emitting an address request command to the at least one slave I2C device;
- at the at least one slave I2C device, responding to the address request command by sending an I2C address of the at least one slave I2C device to the master I2C device;
- arbitrating amongst multiple slave devices that pull the SDA line low at the same time and respond to the address request command from the master I2C device, the arbitration based upon relative values of slave addresses of the multiple slave devices.
A device comprising:
- at least one slave I2C device having an SDA interface for connection to an SDA line and an SCL interface for connection to an SCL line, the at least one slave I2C device being configured to pull the SDA line low to signal an interrupt;
- and
- a master I2C device including an SDA interface for connection to the SDA line and an SCL interface for connection to the SCL line, configured to, after the at least one slave I2C device pulled the SDA line low to signal the interrupt, pull the SCL line low to complete a START and then emit an address request command to the at least one slave I2C device, and receive, in response to the address request command, an I2C address of the at least one slave I2C device.
A device comprising:
- a master I2C device having an SDA interface for connection to an SDA line and an SCL interface for connection to an SCL line, the master I2C device being configured to detect the SDA line being pulled low to signal an interrupt pull the SCL line low in response to detecting the SDA line having been pulled low, and after at least one slave I2C device of multiple slave devices pulled the SDA line low to signal the interrupt, pulling the SCL line low to complete a START and then emitting an address request command to the at least one slave I2C device, and arbitrating amongst the multiple slave devices that pull the SDA line low at the same time and respond with the IRA address request command message, the arbitration based upon relative values of slave addresses of the multiple slave devices;
- and
- a plurality of slave I2C devices, each slave I2C device including a SDA interface for connection to the SDA line and a SCL interface for connection to the SCL line, configured to pull the SDA line low to signal the interrupt, and respond to the address request command by sending an I2C address of the slave I2C device to the master I2C device, wherein there is arbitration among multiple slave devices of the plurality of slave I2C devices that pull the SDA line low at the same time, the arbitration based upon relative values of slave addresses of the multiple slave devices.
Dependencies are inferred from the claim text.