The AWRL684x device includes provision
for an ADC service for user application, where the GPADC engine present inside the device
can be used to measure up to four external voltages. The GPADC1, GPADC2, GPADC3 and GPADC4
pins are used for this purpose.
- GPADC itself is controlled by TI firmware running
inside the FEC subsystem and access to it for customer’s external voltage monitoring
purpose is via ‘APPSS’ calls routed to the FEC subsystem. This API could be linked with
the user application running on APPSS Cortex R5F.
- Device Firmware package (DFP) provides APIs to
configure and measure these signals. The API allows configuring the settling time (number
of ADC samples to skip) and number of consecutive samples to take. Average of the readings
will be reported for each of the monitored voltages.
GPADC structures are used for measuring the output of internal temperature sensors. The accuracy of these measurements is ±7°C.