Asynchronous arbitration of shared resources

A system comprising:

• a first controller configured to selectively operate in a master state in which the first controller controls shared resources and in a standby state in which the first controller does not control the shared resources;
• a second controller configured to selectively operate in the master state in which the second controller controls the shared resources and in the standby state in which the second controller does not control the shared resources;
• a first state control circuit associated with the first controller and comprising a first watchdog timer, the first watchdog timer configured to:
• have an expiration state that is either unexpired or expired;
• and
• generate a first timer status signal indicative of the expiration state of the first watchdog timer;
• a second state control circuit associated with the second controller and comprising a second watchdog timer, the second watchdog timer configured to:
• have an expiration state that is either unexpired or expired;
• and
• generate a second timer status signal indicative of the expiration state of the second watchdog timer;
• wherein the first state control circuit further comprises:
• a first input coupled to the first controller and configured to receive a first request master signal indicative of a request for the first controller to operate in the master state;
• a second input coupled to the second state control circuit and configured to receive the second timer status signal from the second watchdog timer;
• and
• a first master output configured to output a first state status signal based on the first timer status signal and the second timer status signal, the first state status signal indicating whether the first controller is to operate in the master state or the standby state;
• wherein the first watchdog timer comprises:
• a first reset input configured to receive a first reset signal based on the first request master signal and the second timer status signal;
• and
• a first timer output configured to output the first timer status signal;
• and
• wherein selectively:
• the first controller operates in the master state and the second controller operates in the standby state when the first watchdog timer is unexpired and the second watchdog timer is expired;
• the first controller operates in the standby state and the second controller operates in the master state when the first watchdog timer is expired and the second watchdog timer is unexpired;
• and
• both the first and second controllers operate in the standby state when both the first watchdog timer and the second watchdog timer are expired or when both the first watchdog timer and the second watchdog timer are unexpired.