SBOSA45D February 2022 – January 2025 TMP1826
PRODUCTION DATA
The command is used by the host to identify if any of the devices have an alarm condition that must be serviced in alert mode. An alarm condition is set by the device when the temperature conversion is performed and the temperature result is higher than alert high temperature register or lower than alert low temperature register. The command uses the same method as the SEARCHADDR command, except that only devices with an alarm condition shall respond. If none of the devices have an alarm condition, then the host shall get '1' followed by '1' on the bus. If the device sends a '1' followed by '0', the host shall interpret the data as either one or more devices have an alert condition, or all devices have an alert condition. If there is a bus noise, that causes the line to be sample erroneously, but if no device has an alert condition, then the host shall get all '1' on the bus during the address search phase. The ARB_MODE bit does not have an impact on how the subsequent address search algorithm works.
Only devices that have an alert set shall participate when the devices receive an ALERTSEARCH address command and responds by sending the 64-bit address. A device shall no longer participate in the send address phase if the device successfully transmits the device address, which automatically clears the internal alert flags, releases the ALERT pin, until another temperature conversion results in the alert condition getting set. The host controller must verify that all parts on the bus are configured in alert mode to use the command.