6.7.1 EMIF
The EMIF module provides connectivity between DDR memory types and manages data bus read/write accesses between external memory and device subsystems which have master access to the L3_MAIN interconnect and DMA capability.
The EMIF module has the following capabilities:
- Supports JEDEC standard-compliant DDR3/DDR3L-SDRAM memory types
- 2-GiB SDRAM address range over one chip-select. This range is configurable through the dynamic memory manager (DMM) module
- Supports SDRAM devices with one, two, four or eight internal banks
- Supports SDRAM devices with single or dual die packages
- Data bus widths:
- 128-bit L3_MAIN (system) interconnect data bus width
- 128-bit port for direct connection with MPU subsystem
- 32-bit SDRAM data bus width
- 16-bit SDRAM data bus width used in narrow mode
- Supported CAS latencies:
- DDR3: 5, 6, 7, 8, 9, 10 and 11
- Supports 256-, 512-, 1024-, and 2048-word page sizes
- Supported burst length: 8
- Supports sequential burst type
- SDRAM auto initialization from reset or configuration change
- Supports self refresh and power-down modes for low power
- Partial array self-refresh mode for low power.
- Output impedance (ZQ) calibration for DDR3
- Supports on-die termination (ODT) DDR3
- Supports prioritized refresh
- Programmable SDRAM refresh rate and backlog counter
- Programmable SDRAM timing parameters
- Write and read leveling/calibration and data eye training for DDR3.
The EMIF module does not support:
- Burst chop for DDR3
- Interleave burst type
- Auto precharge because of better Bank Interleaving performance
- DLL disabling from EMIF side
- SDRAM devices with more than one die, or topologies which require more than one chip select on a single EMIF channel
For more information, see section DDR External Memory Interface (EMIF) in chapter Memory Subsystem of the device TRM.