Emerson MVME2500 Manuel D’Utilisation

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Programming Model
MVME2500 Installation and Use (6806800L01H)
119
7.6
Other Software Considerations
This section provides programming information in relation to various board components.
7.6.1
MRAM
The MVME2500 provides 512 K bytes of fast, non-volatile storage in the form of 
Magnetoresistive Random Access Memory (MRAM). The MRAM is directly accessible by 
software using processor load and store instructions similar to the DRAM. The difference is that 
the MRAM retains its contents even if the board is power cycled. The MRAM is accessed through 
the LBC.
7.6.2
Real Time Clock
The MVME2500 provides a battery backed-up DS1375 Real Time Clock (RTC) chip. The RTC 
chip provides time keeping and alarm interrupts. It is an I2C device and is accessed through the 
I2C bus address at 0x68.
7.6.3
Quad UART
The MVME2500 console RS232 port is driven by the UART built into the P20x0 QorIQ chip. 
Additionally, the MVME2500 has a Quad UART chip which provides four additional 16550 
compatible UART. These additional UART are internally accessed through the LBC bus. The 
Quad UART chip clock input (which is internally divided to generate the baud rate) is 1.8432 
MHz. The four UART physically connect to RS232 DB9 serial ports through the RTM. 
TSEC2
Gigabit Ethernet port routed to front or back panel, 
set by GBE_MUX_SEL in S2
BCM54616
7
TSEC3
Gigabit Ethernet port routed to back panel
BCM54616
3
Table 7-4 PHY Types and MII Management Bus Address
Ethernet Port
Function / Location
PHY Types
PHY MIIM 
Address