RM0090: Reference manual - STMicroelectronics

RM0090 USB on-the-go high-speed (OTG_HS)
The application can use the following formula to calculate the value of TRDT:
4 × AHB clock + 1 PHY clock = (2 clock sync + 1 clock memory address + 1 clock
memory data from sync RAM) + (1 PHY clock (next PHY clock MAC can sample the 2
clock FIFO outputs)
Figure 397. TRDT max timing case
HCLK
PCLK
tkn_rcvd
dsynced_tkn_rcvd
spr_read
spr_addr
spr_rdata
srcbuf_push
srcbuf_rdata
31.13.9 OTG programming model
0ns 50ns 100ns 150ns 200ns
1 2 3 4 5 6 7 8
The OTG_HS controller is an OTG device supporting HNP and SRP. When the core is
connected to an “A” plug, it is referred to as an A-device. When the core is connected to a
“B” plug it is referred to as a B-device. In host mode, the OTG_HS controller turns off V BUS
to conserve power. SRP is a method by which the B-device signals the A-device to turn on
V BUS power. A device must perform both data-line pulsing and V BUS pulsing, but a host can
detect either data-line pulsing or V BUS pulsing for SRP. HNP is a method by which the Bdevice
negotiates and switches to host role. In Negotiated mode after HNP, the B-device
suspends the bus and reverts to the device role.
A1
5 Clocks
D1
Doc ID 018909 Rev 3 1306/1416
D1
ai15680