Pi 2 Design Mercury Streamer, Hardware Reference Manual – P8
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7
MERCURY STREAMER SOFTWARE
7.1
OVERVIEW
Due to the various resources interfaced on the Mercury Streamer, both internal and
external to the CM4, it is necessary to initialize a large number of CPU registers and
external devices before correct operation can begin. These values and their proper
sequencing are beyond the scope of this document.
7.2
COMPATIBLE DRIVER
Most Audio Player software will support Mercury using either the “Pi2design PI2AES” or
“HifiBerry Digi+ Pro” driver.
7.3
USB HOST
Unlike the Raspberry Pi 4, the CM4 ROM Firmware does not enable the USB Host
functionality by default. It is necessary to initialize this by adding the following line to
cfg_boot.txt. Note that some player software will over-write this during an update but
may offer an alternate location that is safe from updates.
To enable the USB 2.0 ports on the Compute Module 4, you need to edit the boot config
file (/boot/config.txt) and add:
dtoverlay=dwc2,dr_mode=host
7.4
PCIE SSD CONFIGURATION
This section is %TBD%
