DSS Networks 8261-RTM - Manual (Page 57)

Gigabit Ethernet Metro-Switch Board and Firmware Users Manual
DSS NETWORKS, INC. Version: 1.14g Page: 57
10. ON BOARD FIRMWARE
10.1 INTRODUCTION
The Metro-Switch has an onboard 16-bit RISC microcontroller and uses the Motorola
DSP56F826 hybrid DSP/microcontroller for onboard management functions. The
DSP56F826 is useful for a local switch management processor because it contains
more features than found in conventional microcontrollers. It has a 16-bit bus interface
unit suitable for external devices including SRAM and also has a JTAG interface
suitable for use with a JTAG debugger.
The microcontroller switch management processor contains the following features:
ƒ 80 MHZ operation
ƒ 40 MIPS
ƒ 16-bit external bus interface unit
ƒ I2C communications to BCM5690 switch at 100KHZ (12 Kbytes/sec)
ƒ 128K words (256KB) of SRAM for code and data
ƒ 16K bytes of EEPROM for switch configuration
ƒ JTAG port connected to 14-pin onboard header
ƒ 3 general purpose LEDS (used for run-state)
ƒ RS232 serial port connected to onboard RJ-11
The microcontroller interfaces to the Broadcom BCM5690 switch via the I2C interface.
This interface runs at 100KHZ and provides a register read/write access with a
bandwidth of 100Kb (12KB/sec).
The microcontroller also controls each of the four Broadcom BCM5464SR quad-port
transceivers by accessing them via the “MI” interface by going indirectly through the
switch.
The microcontroller interfaces to the 128 KB general purpose non-volatile storage
EEPROM via the I2C interface and interfaces to the 128KB SRAM via the 16-bit
external bus interface. There is also a serial RS232 com port for the CLI command line
interface and 3-LEDS are also accessible and controlled from the microcontroller.