AN2295 Freescale Semiconductor / Motorola, AN2295 Datasheet - Page 48

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

PC Bootloader Master Software
Initial Hook (Waiting for MCU Reset)
Immediately after all initializations are done in the PC, a loop is started to wait for communication from the
MCU. The
communication with the MCU.
Checking ACK
A routine,
of characters that can be received due to a communication speed mismatch (See
Communication
Speed Calibration
A speed calibration loop, implemented in the
described in
is sent.
MCU Info Reading
Immediately after the calibration is successfully completed, the PC requests the
the MCU responds with information about itself. This is achieved in the
routine.
Image Manipulations
The two functions,
Image
Block Operations
Three main data exchange operations are performed:
These basic operations are implemented in the functions:
int erase_blk(unsigned a)
int read_blk(unsigned adr, int len, BYTE *dest)
int prg_blk(unsigned a, int len)
The actual implementation is straight-forward and follows the rules described in
Commands.
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•
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Erase block
Read block
Write (program) block
Operations.
int could_be_ack(unsigned b)
int hook_reset(void)
Slave Frequency
Speed).
int setup_vect_tbl(void)
Developer’s Serial Bootloader for M68HC08 and HCS08 MCUs, Rev. 6
Calibration. If no ACK is received from the MCU, another break character
routine implements all necessary steps to establish initial
int calibrate_speed(void)
, checks whether a received character fits the possible set
and
int check_image(),
int read_mcu_info(void)
routine, follows the scenario
are described in
Ident
Interpreting MCU
Unknown MCU
Freescale Semiconductor
Command, to which
8-Bit MCU