Advance Information
• Enhanced 8-bit C500 CPU
   – Full software/toolset compatible to standard 80C51/80C52 microcontrollers
• 12 MHz external operating frequency
   – 500 ns instruction cycle
• Built-in PLL for USB synchronization
• On-chip OTP program memory
   – C540U : 4K byte
   – C541U : 8K byte
   – Alternatively up to 64K byte external program memory
   – Optional memory protection
• On-chip USB module
   – Compliant to USB specification
   – Full speed or low speed operation
   – Five endpoints : one bidirectional control endpoint four versatile programmable endpoints
   – Registers are located in special function register area
   – On-chip USB transceiver
  
Features:
• Up to 64K byte external data memory
• 256 byte on-chip RAM
• Four parallel I/O ports
   – P-LCC-44 package : three 8-bit ports and one 6-bit port
   – P-SDIP-52 package : four 8-bit ports
   – LED current drive capability for 3 pins (10 mA)
• Two 16-bit timer/counters (C501 compatible)
• SSC synchronous serial interface (SPI compatible) (only C541U)
   – Master and slave capable
   – Programmable clock polarity / clock-edge to data phase relation
   – LSB/MSB first selectable
   – 1.5 MBaud transfer rate at 12 MHz operating frequency
• 7 interrupt sources (2 external, 5 internal with 2 USB interrupts) selectable at 2 priority levels
• Enhanced fail safe mechanisms
   – Programmable watchdog timer (only C541U)
   – Oscillator watchdog
• Power saving modes
   – idle mode
   – software power down mode with wake-up capability through INT0 pin or USB
• On-chip emulation support logic (Enhanced Hooks Technology TM)
• P-LCC-44 and P-SDIP-52 packages
• Power supply voltage range : 4.0V to 5.5V
• Temperature Range : SAB-C540U TA = 0 to 70 °C
                               SAB-C541U T A = 0 to 70 °C