HCS12X core at 50 MHz — memory map and peripheral fit
The MC9S12XET256MAL is a 16-bit microcontroller from NXP's HCS12X family, built around the HCS12X core clocked at 50 MHz. It carries 256 KB of program flash, 16 KB of RAM, and 4 KB of EEPROM on-chip — enough headroom for a body-controller or gateway application running a real-time OS with a moderate CAN message buffer. The 91 general-purpose I/O lines, combined with the CAN, SPI, I²C, SCI, and external bus interface, cover the typical peripheral set for automotive body electronics or industrial I/O modules. The 12-channel 12-bit ADC handles analog sensor inputs without an external converter.
Supply voltage and temperature grade — single-rail, wide-range operation
The 112-LQFP package (20x20 mm body) with 0.65 mm pitch requires a 4-layer PCB for clean fan-out of the 91 I/O and the external bus signals.