VRS51L3174 pdf datasheet (High

The VRS51L3174 is a high performance, 8051-based microcontroller
coupled with a fully integrated array of peripherals for addressing a
broad range of embedded design applications.
Based on a powerful 40-MIPS, single-cycle, 8051 microprocessor,
the VRS51L3174’s memory sub-system features 64KB of Flash
and 4352 bytes of SRAM and 8192 Bytes of nonvolatile FRAM
(ferroelectric random access memory) memory.
Support peripherals include a hardware based arithmetic unit capable
of performing complex mathematical operations, a JTAG interface for
Flash programming and non-intrusive in-circuit debugging/emulation,
an internal oscillator, and a watchdog timer.
Communication and control of external devices is facilitated via an
assortment of digital peripherals such as an enhanced, fully
configurable SPI bus, an I2C interface, dual UARTs with dedicated
baud rate generators, three 16-bit timers, 8 PWM controllers each
with a 16-bit timer, and 2 pulse width counter modules.
The VRS51L3174 operates from 3.0 to 3.6 volts over the industrial
temperature range and is available in a QFP-44 package. The device
features an active-low reset and is pin-compatible with an industry
standard 8051 microcontroller footprint.