Figure 427. Trdt Max Timing Case - STMicroelectronics STM32F405 Reference Manual

RM0090
Once the MAC receives an IN token, this information (token received) is synchronized to the
AHB clock by the PFC (the PFC runs on the AHB clock). The PFC then reads the data from
the SPRAM and writes them into the dual clock source buffer. The MAC then reads the data
out of the source buffer (4 deep).
If the AHB is running at a higher frequency than the PHY, the application can use a smaller
value for TRDT (in OTG_HS_GUSBCFG).
Figure 427
•
tkn_rcvd: Token received information from MAC to PFC
• dynced_tkn_rcvd: Doubled sync tkn_rcvd, from PCLK to HCLK domain
•
spr_read: Read to SPRAM
• spr_addr: Address to SPRAM
•
spr_rdata: Read data from SPRAM
• srcbuf_push: Push to the source buffer
•
srcbuf_rdata: Read data from the source buffer. Data seen by MAC
Refer to
tkn_rcvd
dsynced_tkn_rcvd
spr_read
spr_addr
spr_rdata
srcbuf_push
srcbuf_rdata
has the following signals:
Table 208: TRDT values

Figure 427. TRDT max timing case

0ns
1 2
HCLK
PCLK
DocID018909 Rev 11
USB on-the-go high-speed (OTG_HS)
for the values of TRDT versus AHB clock frequency.
50ns 100ns
3 4
A1
5 Clocks
150ns 200ns
5 6 7
D1
D1
8
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