SPRUJ53B April 2024 – September 2024 TMS320F28P550SJ , TMS320F28P559SJ-Q1
FILE: lpm_ex6_haltwake_gpio_watchdog.c
This example puts the device into HALT mode. If the lowest possible current consumption in HALT mode is desired, the JTAG connector must be removed from the device board while the device is in HALT mode.
For applications that require minimal power consumption during HALT mode, application software should power off the XTAL prior to entering HALT by setting the XTALCR.OSCOFF bit or by using the driverlib function SysCtl_turnOffOsc(SYSCTL_OSCSRC_XTAL);. If the OSCCLK source is configured to be XTAL, the application should first switch the OSSCLK source to INTOSC1 or INTOSC2 prior to setting XTALCR.OSCOFF.
This example puts the device into HALT mode and then wakes up the device from HALT using an LPM wakeup pin.
The pin GPIO0 is configured as the LPM wakeup pin to trigger a WAKEINT interrupt upon detection of a low pulse.The GPIO0 pin must be pulled from high to low by an external agent for wakeup.
In this example, the watchdog timer is clocked, and is configured to produce watchdog reset as a timeout mechanism.
GPIO1 is pulled high before entering the STANDBY mode and is pulled low when in the wakeup ISR.
External Connections