MCBSTM32EXL Keil, MCBSTM32EXL Datasheet - Page 847

• Manufacturer Part Number: MCBSTM32EXL
• Description: BOARD EVALUATION FOR STM32F103ZE
• Manufacturer: Keil

Specifications of MCBSTM32EXL

• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

RM0008
27.4.3
Figure 289. MII clock sources
Reduced media-independent interface: RMII
The reduced media-independent interface (RMII) specification reduces the pin count
between the STM32F20xxx Ethernet peripheral and the external Ethernet in 10/100 Mbit/s.
According to the IEEE 802.3u standard, an MII contains 16 pins for data and control. The
RMII specification is dedicated to reduce the pin count to 7 pins (a 62.5% decrease in pin
count).
The RMII is instantiated between the MAC and the PHY. This helps translation of the MAC’s
MII into the RMII. The RMII block has the following characteristics:
●
●
●
●
Figure 290. Reduced media-independent interface signals
It supports 10-Mbit/s and 100-Mbit/s operating rates
The clock reference must be doubled to 50 MHz
The same clock reference must be sourced externally to both MAC and external
Ethernet PHY
It provides independent 2-bit wide (dibit) transmit and receive data paths
25 MHz
STM32
STM32
Ethernet (ETH): media access control (MAC) with DMA controller
HSE
MCO
Doc ID 13902 Rev 9
Clock source
REF _CLK
TXD[ 1:0]
RXD[1:0]
CRS_ DV
MDIO
TX _CLK
RX _CLK
MDC
TX_EN
25 MHz
External
PHY
25 MHz
External
PHY
For 10/100 Mbit/s
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