M68HC11 E series of 8-bit microcontroller units (MCUs) combine 
the M68HC11 central processor unit (CPU) with high-performance, 
on-chip peripherals.
The E series is comprised of many devices with various configurations of:
* Random-access memory (RAM)
* Read-only memory (ROM)
* Erasable programmable read-only memory (EPROM)
* Electrically erasable programmable read-only memory (EEPROM)
* Several low-voltage devices are also available.
With the exception of a few minor differences, the operation of all E-series MCUs
is identical. A fully static design and high-density complementary metal-oxide
semiconductor (HCMOS) fabrication process allow the E-series devices to operate
at frequencies from 3 MHz to dc with very low power consumption.

Features
Features of the E-series devices include:
* M68HC11 CPU
* Power-saving stop and wait modes
* Low-voltage devices available (3.0-5.5 Vdc)
* 0, 256, 512, or 768 bytes of on-chip RAM, data retained during standby
* 0, 12, or 20 Kbytes of on-chip ROM or EPROM
* 0, 512, or 2048 bytes of on-chip EEPROM with block protect for security
* 2048 bytes of EEPROM with selectable base address in the MC68HC811E2
* Asynchronous non-return-to-zero (NRZ) serial communications interface
(SCI)
* Additional baud rates available on MC68HC(7)11E20
* Synchronous serial peripheral interface (SPI)
* 8-channel, 8-bit analog-to-digital (A/D) converter

16 General Description MOTOROLA
* 16-bit timer system:
- Three input capture (IC) channels
- Four output compare (OC) channels
- One additional channel, selectable as fourth IC or fifth OC
* 8-bit pulse accumulator
* Real-time interrupt circuit
* Computer operating properly (COP) watchdog system
* 38 general-purpose input/output (I/O) pins:
- 16 bidirectional I/O pins
- 11 input-only pins
- 11 output-only pins

* Several packaging options:
- 52-pin plastic-leaded chip carrier (PLCC)
- 52-pin windowed ceramic leaded chip carrier (CLCC)
- 52-pin plastic thin quad flat pack, 10 mm x 10 mm (TQFP)
- 64-pin quad flat pack (QFP)
- 48-pin plastic dual in-line package (DIP), MC68HC811E2 only
- 56-pin plastic shrink dual in-line package, .070-inch lead spacing (SDIP)