Technical data

Programming Model
MVME2502 Installation and Use (6806800R96B)
135
7.6 Other Software Considerations
The following sections provide programming information in relation to various board
components:
7.6.1 MRAM
The MVME2502 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 MVME2502 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 MVME2502 console RS232 port is driven by the UART built into the P2020 QorIQ chip.
Additionally, the MVME2502 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