RM0390 Rev 4 1079/1328
RM0390 USB on-the-go full-speed/high-speed (OTG_FS/OTG_HS)
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31.2.1 General features
The OTG_FS/OTG_HS interface general features are the following:
• It is USB-IF certified to the Universal Serial Bus Specification Rev 2.0
• OTG_HS supports the following PHY interfaces:
– An on-chip full-speed PHY
– An ULPI interface for external high-speed PHY
• It includes full support (PHY) for the optional On-The-Go (OTG) protocol detailed in the
On-The-Go Supplement Rev 2.0 specification
– Integrated support for A-B device identification (ID line)
– Integrated support for host Negotiation protocol (HNP) and session request
protocol (SRP)
– It allows host to turn V
BUS
off to conserve battery power in OTG applications
– It supports OTG monitoring of V
BUS
levels with internal comparators
– It supports dynamic host-peripheral switch of role
• It is software-configurable to operate as:
– SRP capable USB FS/HS Peripheral (B-device)
– SRP capable USB FS/HS/LS host (A-device)
– USB On-The-Go Full-Speed Dual Role device
• It supports FS/HS SOF and LS Keep-alives with
– SOF pulse PAD connectivity
– SOF pulse internal connection to timer (TIMx)
– Configurable framing period
– Configurable end of frame interrupt
• OTG_HS embeds an internal DMA with shareholding support and software selectable
AHB burst type in DMA mode.
• It includes power saving features such as system stop during USB suspend, switch-off
of clock domains internal to the digital core, PHY and DFIFO power management.
• It features a dedicated RAM of 1.25[FS] / 4[HS] Kbytes with advanced FIFO control:
– Configurable partitioning of RAM space into different FIFOs for flexible and
efficient use of RAM
– Each FIFO can hold multiple packets
– Dynamic memory allocation
– Configurable FIFO sizes that are not powers of 2 to allow the use of contiguous
memory locations
• It guarantees max USB bandwidth for up to one frame (1 ms) without system
intervention.