50 MHz Cortex-M3 with integrated Ethernet MAC
The integrated Ethernet MAC (with MII/RMII) is the headline peripheral — it saves an external chip for 10/100 industrial Ethernet nodes.
Obsolete — last-time-buy and sourcing reality
The Stellaris family was acquired by TI and later phased out in favor of the Tiva-C and TM4C series. There is no official pin-compatible drop-in replacement from TI; the TM4C123x or TM4C129x families offer similar peripherals but in different package options and with a 3.3 V supply.
Peripherals and on-chip resources
Beyond the Ethernet MAC, the LM3S6965 includes a 4-channel 10-bit ADC, PWM outputs, a watchdog timer, and an internal oscillator. The 64 KB SRAM is organized as 64K x 8, adequate for moderate-size packet buffers. The 42 I/O pins are 5 V tolerant on most ports, simplifying level translation when interfacing to legacy 5 V logic or sensors.