AN2295 Freescale Semiconductor / Motorola, AN2295 Datasheet - Page 42

• Manufacturer Part Number: AN2295
• Description: Developers Serial Bootloader for M68HC08 and HCS08 MCUs
• Manufacturer: Freescale Semiconductor / Motorola

MCU Slave Software
The master side of the bootloader must be informed that the single-wire communication is used. This can
be done by calling the hc08sprg.exe software. Use the following extended calling convention:
hc08sprg.exe 1:S filename.s19
Original (old) format:
Now defaults to:
hc08sprg.exe 1:? filename.s19
The detection is only possible if the serial interface (mainly the level shifter) is powered up and working
BEFORE the bootloading process starts. Because this is not usually the case, always specify the
bootloading mode by including either a “:S” or a “:D” in the parameter.
MC68HC908LJ
MC68HC908LJ MCUs are members of the M68HC08 Family used to drive LCD displays. MC68HC908LJ
MCUs have the ROM on-chip FLASH programming routines available. The calling convention is slightly
different from other M68HC08s (see MC68HC908LJ data sheet, monitor ROM section).
MC68HC908LJ MCUs are primarily targeted for use with a low-cost 32.768 kHz crystal. Because the
frequency of the crystal is known, no calibration is performed, which saves MCU memory. Therefore,
these MCUs use the
MC68HC908AP
MC68HC908AP devices are members of the M68HC08 Family that have two SCIs (the SCI channel must
be selected at compile time). MC68HC908AP MCUs have ROM on-chip FLASH programming routines
available. The calling convention is slightly different from other M68HC08s (same as MC68HC908LJ
devices).
Because of the simplicity of the internal oscillator, it does not have the accuracy and stability of the RC
oscillator or the XTAL oscillator. Therefore, the internal oscillator is not suitable if an accurate bus clock
is required and it should not be used as the source for the bus clock.
A low-cost 32.768 kHz crystal was selected as default source clock for the bootloader and user
application. Because the frequency of the crystal is known, no calibration is performed, which saves MCU
memory. Therefore, these MCUs use the
MC68HC908AB/AS/AZ
MC68HC908AB/AS/AZ devices are members of the M68HC08 Family that have (in addition) EEPROM
memory. This code also demonstrates the way how to program these EEPROM cells using AUTO
(automatic clear of EEPGM) mode.
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where 1 specifies which COM port is used for communication, and S stands for single-wire.
where D stands for dual-wire mode. The bootloader master can also detect the presence of a
single-wire interface if called:
Known MCU Communication Speed
Developer’s Serial Bootloader for M68HC08 and HCS08 MCUs, Rev. 6
hc08sprg.exe 1 filename.s19
hc08sprg.exe 1:D filename.s19
Known MCU Communication Speed
method.
method.
Freescale Semiconductor