VRS51C540 Datasheet | Ramtron

Overview The VRS51x540 is a low cost 8-bit microcontroller based on the standard 80C51 microcontroller family architecture. It is pin patible and is a drop-in replacement for standard 8051 MCUs Aimed at cost effective applications requiring small amounts of program/data memory coupled with streamlined peripheral support, the VRS51x540 includes 4KB of Flash memory, 128 bytes of RAM a UART, three 16-bit timers, a Watchdog timer and power down features . The VRS51x540 is available in 5 (VRS51C540) and 3.3 (VRS51L540) volt versions in PLCC-44, QFP-44 and DIP-40 packages. The VRS51x540 devices operate over the entire industrial temperature range. The Flash memory can be programmed using programmers available from Ramtron or other 3rd party mercial programmers. FIGURE 1: VRS51X540 FUNCTIONAL DIAGRAM P1.2 T2EX/P1.1 Feature Set - - - - - - - - - - - - - - - - - - - 80C51/80C52 pin patible 12 clock periods per machine cycle 4KB on-chip Flash memory 128 bytes on-chip data RAM 32 I/O lines: P0-P3 = 8-bit Full duplex serial port (UART) 3, 16-bit Timers/Counters Watchdog Timer 8-bit Unsigned Division / Multiply BCD arithmetic Direct and Indirect Addressing Two levels of interrupt priority and nested interrupts Power saving modes Code protection function Operates at a clock frequency of up to 40MHz Low EMI (inhibit ALE) Programming voltage: 12V Industrial Temperature range (-40°C to +85°C) 5V and 3V versions available (see ordering information.) FIGURE 2: VRS51X540 PLCC AND QFP PINOUT DIAGRAMS P0.0/AD0 P0.2/AD2 8051 PROCESSOR P1.5 P0.3/AD3 40 39 P0.1/AD1 T2/P1.0 P1.3 P1.4 P0.4/AD4 P0.5/AD5 P0.6/AD6 P0.7/AD7 #EA NC ALE #PSEN P2.7/A15 ADDRESS/ DATA BUS P1.6 P1.7 RESET RXD/P3.0 4KB FLASH 128 Bytes of RAM PORT 0 NC TXD/P3.1 #INT0/P3.2 #INT1/P3.3 T0/P3.4...