System Controller: Internal (IDMA) Controller

Device Control Registers

Each bank has its own parameters register and can be programmed to 8, 16, or 32-bits wide. The device interface consists of 128 bytes of write buffer and 128 bytes of read buffer.

INTERNAL (IDMA) CONTROLLER

Each of the four DMA engines can move data between any source and any destination, such as the SDRAM, device, PCI_0, or CPU bus. These engines optimize system performance by moving large amounts of data without significant CPU intervention. Read and write are handled independently and concurrently.

Timer/Counter

Each of the four 32-bit wide timer/counters can be selected to operate as a timer or a counter. Each timer/counter increments with every TCLK rising edge. In counter mode, the counter counts down to terminal count, stops, and issues an interrupt. In timer mode, the timer counts down, issues an interrupt on terminal count, reloads itself to the programmed value, and continues to count. Reads from the counter or timer are completed directly from the counter, and writes are to the timer/counter register.

PCI INTERFACE

The Emerson PmPPC7448 module complies with the PCI mezzanine card (PMC) form factor for peripheral component interconnect (PCI) modules and the specification for Processor PCI Mezzanine Cards (PPMC). The MV64460 supports two 64-bit PCI interfaces, compliant to the PCI Local Bus Specification revision 2.3. Only PCI0 is functional on the PmPPC7448. Other features include:

Support for PCI-to-PCI memory, I/O, and configuration transactions between the two PCI interfaces

Support for PCI-to-PCI-X bridging between the two PCI interfaces

PCI bus speed up to 66 MHz in conventional PCI mode or up to 133 MHz in PCI-X mode

When both PCI interfaces are functional, they operate in asynchronous clocks to each other and to the MV64460 core clock

32/64-bit PCI master and target operations

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PmPPC7448 User’s Manual

10006757-02

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Emerson PMPPC7448 System Controller Internal Idma Controller, Device Control Registers, Timer/Counter, PCI Interface