HMS99C51

• Fully compatible to standard MCS-51 microcontroller
• Wide operating frequency up to 40MHz
   (for more detail, see “HMS99C5X Series Selection Guide”)
• X2 Speed Improvement capability ( X2 Mode : 6 clocks/machine cycle)
   20MHz @5V (Equivalent to 40MHz @5V)
• 4K bytes FLASH ROM
• 128 × 8Bit RAM
• 64K external program memory space
• 64K external data memory space
• Four 8-bit ports
• Two 16-bit Timers / Counters
• USART
• Programmable ALE pin enable / disable (Low EMI)
• Five interrupt sources, two priority levels
• Power saving Idle and power down mode
• P-DIP-40, P-LCC-44, P-MQFP-44 package
• Temperature Ranges : -40°C ~ 85°C

HMS99C52

• Fully compatible to standard MCS-51 microcontroller
• Wide operating frequency up to 40MHz
   (for more detail, see “HMS99C5X Series Selection Guide”)
• X2 Speed Improvement capability ( X2 Mode : 6 clocks/machine cycle)
   20MHz @5V (Equivalent to 40MHz @5V)
• 8K bytes FLASH ROM
• 256 × 8Bit RAM
• 64K external program memory space
• 64K external data memory space
• Four 8-bit ports
• Three 16-bit Timers / Counters (Timer2 with up/down counter feature)
• USART
• One clock output port
• Programmable ALE pin enable / disable (Low EMI)
• Six interrupt sources, two priority levels
• Power saving Idle and power down mode
• P-DIP-40, P-LCC-44, P-MQFP-44 package
• Temperature Ranges : -40°C ~ 85°C