in ADSP-SC58x, HADC provides 8 channels which can be sampled sequentially. If more channels are desired, HADC provides an option to extend the number of channels to 15 by using the external multiplexer. To do this channel 8 of ADC is extended to 8 more additional channels via multiplexer which is controlled through 3 mux pins. For the code, the data from additional channels is stored in HADC DATA registers similar to how it is stored for default channels. There are 15 DATA register each for one HADC channel.
About 3 pins which control external mux: To which pins of ADSP-SC5xx should they be connected?
Any 3 port GPIO is accepatble?
HRM shows ADC_EXT_INTERFACE[0:3] should drive these 3 pins.
There are dedicated pins in the GPIO space which control these external MUX interface pins.
They appear on the PORTF as shown in the screenshot. you need to configure the GPIO FER and MUX registers to selects these pins for HADC functionality.
We are using SC584 which dose not have PORT_F.
How should we drive external MUX?