These devices can address up to 64 Kbytes of external program/data memory.
The Intel 8XL52/8XL54/8XL58 is a single-chip control oriented microcontroller which is fabricated on Intel’s reliable CHMOS III-E technology. Being a member of the MCS 51 microcontroller family, the 8XL52/8XL54/8XL58 uses the same powerful instruction set, has the same architecture, and is pin-for-pin compatible with the existing MCS 51 microcontroller products

■ High Performance CHMOS OTP ROM
■ Low Voltage Operation
■ 20 MHz Commercial/16 MHz Express Operation
■ Three 16-Bit Timer/Counters
■ Up/Down Timer/Counter
■ Three Level Program Lock System
■ 8K/16K/32K On-Chip Program Memory
■ 256 Bytes of On-Chip Data RAM
■ Improved Quick Pulse Programming Algorithm
■ Boolean Processor
■ 32 Programmable I/O Lines
■ 6 Interrupt Sources
■ Four Level Interrupt Priority
■ Programmable Serial Channel with:
    — Framing Error Detection
    — Automatic Address Recognition
■ 64K External Program Memory Space
■ 64K External Data Memory Space
■ MCSÉ 51 Microcontroller Compatible Instruction Set
■ Power Saving Idle and Power Down Modes
■ ONCE (On-Circuit Emulation) Mode
■ Extended Temperature Range (b40§C to a85§C)