78Q8430 STEM Demo Board User Manual (78Q8430STEM-DB) (78Q8430STEM-DB)

The 78Q8430 STEM Demo Board (D8430T3B_STEM) is a design example for a 10/100BASE-TX MAC+PHY ST Microelectronics STEM daughter card. The Demo Board plugs directly into STi5100 and STi5514 Evaluation Systems. The network connection is provided by the 78Q8430 which is a single chip auto-sensing, auto-switching (auto-negotiation or parallel detect modes and auto-MDIX) 10/100BASE-TX Fast Ethernet transceiver with full duplex operation capability. The device is designed specifically for the Audio/Visual (A/V) and Set Top Box (STB) markets and is easily interfaced to available A/V and STB core processors.

The 78Q8430 is compliant with applicable IEEE®-802.3 standards. MAC and PHY configuration and status registers are provided as specified by IEEE 802.3u. The integrated MAC is supported by an internal 32KByte transmit and receive SRAM FIFO. The partition of transmit and receive queues are configurable through software, allowing the 78Q8430 to be tuned for specific applications. The device contains hardware support for TCP-IP checksum and ARC address recognition.


  • The system bus interface operates like external memory with an active low chip select.
  • A configurable bus interface with support for little endian and big endian formats.
  • Supports an asynchronous 100 MHz (max) bus clock for STi5100/5514 operation.
  • Supports 32-bit, 16-bit and 8 bit wide data bus formats.
  • Optional EEPROM interface for configuration data.
  • Two programmable LED outputs for PHY status.
  • Single +3.3V power supply voltage with common ground plane.