SLUUB65B May 2015 – December 2022
The default fuel gauge behaves as an HDQ slave-only device when HDQ mode is enabled. If the HDQ interrupt function is enabled, the fuel gauge is capable of mastering and also communicating to an HDQ device. There is no mechanism for negotiating what is to function as the HDQ master and care must be taken to avoid message collisions. The interrupt is signaled to the host processor with the fuel gauge mastering an HDQ message. This message is a fixed message that will be used to signal the interrupt condition. The message itself is 0x80 (slave write to register 0x00) with no data byte being sent as the command is not intended to convey any status of the interrupt condition. The HDQ interrupt function is disabled by default and needs to be enabled by command and Pack Configuration [HOST_IE] should be set to 1.
When the SET_HDQINTEN subcommand is received, the fuel gauge will detect any of the interrupt conditions as specified in Table 6-5 and assert the interrupt at 1-second intervals until the CLEAR_HDQINTEN command is received or the count of HDQHostIntrTries has lapsed.
The number of tries for interrupting the host is determined by the data flash parameter named HDQHostIntrTries.