深圳市昌宏瑞科技有限公司

General Description 

The RTL8231 is an SMI (Serial Management Interface) Slave, MIIM (Media Independent Interface Management), and Shift Register LED display controller that transmits:

 • SMI Slave/MIIM Data to Scan LED 

• SMI Slave/MIIM Data to GPIO 

• Parallel LED output via Shift Register Mode 

SMI Slave/MIIM Data to Scan LED In this mode, the RTL8231 supports SMI Slave and MIIM bus data formats. In SMI Slave mode, 8-bit and 16-bit data accesses are both supported. The SMI Slave or MIIM interface can set the address from 0 to 7 (SMI Slave) or from 0 to 31 (MIIM). The RTL8231 controls Scan LEDs and GPIOs via LED and GPIO status registers. Single-Color Scan LED supports two configurations: 

 • 24-port*3-LED=72 LEDs (max) 

• 24-port*2-LED+8-port*(1 bi-color+1 single-color LED)=64 LEDs (for 24-port Fast Ethernet + 8-port Gigabit Ethernet) Bi-Color Scan LED supports maximal 24-port applications: 

 • 24-port*(1 bi-color+1 single-color LED)=48pcs LEDs (max) SMI Slave/MIIM Data to GPIO The RTL8231 provides 37 GPIOs. Any unused Single-color or Bi-color LED pin can be switched to become a GPIO pin Shift Register Mode In Shift Register Mode, the RTL8231 supports 36 LEDs. The RTL8231 receives serial data and serial clock, and via the shift register changes it to parallel output. The SO (Serial Out) pin outputs any serial data input that exceeds 36 bits for cascading to another RTL8231. The Reset pin clears the shift register data, and the strapping pin sets the initial values when the RTL8231 is reset.