Changes

*tWD = 10s(the exhaustive list of configurations options is descripted in table 1 of reference <ref name="MAX6373"></ref>).In other words, WDT is started when the first transition on WDI input is detected. Once started, its timeout period is 10s. The first transition of WDI input should be under software control. However, despite of the presence of 22kOhm pull-down on EX_WDT_REARM signal, during power-on sequence a spurious 0-to-1 transition may be observed on EX_WDT_REARM lineWDI input. The voltage swing of this transition is variable, since it depends on the internal Zynq's pull-up valueof PS_MIO15_500 pad. In general, <u>WDT may be inadvertently started at power-up</u>, before software takes control of PS_MIO15_500 GPIO. <u>To avoid this situation, it is recommended to add a 2.2kOhm pull-down on carrier board, connected to the PS_MIO15_500 signal</u>.

Since WD_SETx signals are routed externally, WDT configuration can be changed by optional circuitry implemented on the carrier board. Different solutions for the watchdog management can be implemented on the carrier board, depending on system requirements. The easiest circuit consists of additional pull-up/down resistors connected to WD_SETx pins in order to overrule default configuration. The exhaustive configurations options are listed in table 1 of reference <ref name="MAX6373"></ref>.