Specifications

ASMi-52CD Ver. 1.0 CPU and Memory Elements B-1
Appendix B
Memory and Download
B.1 CPU and Memory Elements
The ASMi-52CD flash contains the following elements:
• Boot Flash – Contains the Boot program, essential for the modems initial
operations.
• Flash – Contains the application program in a compressed state. The boot
program decompresses the application to the DRAM.
• DRAM – Contains the application while it runs, and all the data and variables
the program requires for operation.
• Peripherals – Include the SHDSL chipset, the LEDs and other on-board
components. The CPU can access these components.
• CPU – The main processing unit of the modem – responsible for all control,
monitoring and operation of the modem.
• FPGA – Responsible for glue logic and proprietary timing implementations.
The CPU first runs the Boot program from the Boot Flash. The Boot program then
decompresses one of the two compressed application programs stored in Flash to
the DRAM. The uncompressed program runs from the DRAM, and loads the FPGA.
This enables the CPU to access all the peripheral devices and begin to run the
modem.
CPU
FPGA
DRAM
Periferals
(LEDS,
SHDSL chipsets
and others)
FLASH
Boot
Flash
Figure B-1. Memory Map