MC68HC05X4 Datasheet, PDF (20/156 Pages) Motorola, Inc – HCMOS Microcontroller Unit

Freescale Semiconductor, Inc.
Modes of Operation and Pin Descriptions
Bootloader
functions
The bootloader code deals with the copying of user code from an
external EPROM into the on-chip EPROM. The bootloader function can
only be used with an external EPROM. The bootloader performs a
programming pass and then does a verify pass.
Pins PB3 and PB4 are used to select various bootloader functions,
including the programming mode (see Figure 4). Two other pins, PB1
and PB6, are used to drive the PROG and VERF LED outputs. While the
EPROM is being programmed the PROG LED flashes and when
programming is complete the VERF LED flashes.
MC68HC05X4 Rev 1.0
20
Modes of Operation and Pin Descriptions
For More Information On This Product,
Go to: www.freescale.com
8-modes
MOTOROLA