MC68HC705 MOTOROLA [Motorola, Inc], MC68HC705 Datasheet - Page 113

• Manufacturer Part Number: MC68HC705
• Description: HCMOS Microcontroller Unit
• Manufacturer: MOTOROLA [Motorola, Inc]

9.4.7 Execute Program in RAM
9.4.8 Dump PROM Contents
MC68HC705C8A — Rev. 2.0
MOTOROLA
NOTE:
This routine allows the MCU to transfer control to a program previously
loaded in RAM. This program is executed once bootstrap mode is
entered, if switch S6 is in the ON position and switch 2 is in the OUT
position, without any firmware initialization. The program must start at
location $0051 to be compatible with the load program in RAM routine.
To run the execute program in RAM routine, take these steps:
The non-programmable watchdog COP is disabled in bootloader mode,
even if the NCOPE bit is programmed.
In the dump PROM contents routine, the PROM contents are dumped
sequentially to the SCI output, provided the PROM has not been
secured. The first location sent is $0020 and the last location sent is
$1FFF. Unused locations are skipped so that no gaps exist in the data
stream. The external memory address lines indicate the current location
being sent. Data is sent with eight data bits and one stop bit at 4800 baud
with a 2-MHz crystal or 9600 baud with a 4-MHz crystal.
To run the dump PROM contents routine, take these steps:
1. Set switch 1 in the ON position (restores V
2. Connect V
3. Set switch S6 in the OFF position.
4. Switches S3, S4, and S5 can be in either position.
5. Set switch 2 in the OUT position (routine is activated).
1. Set switch 1 in the ON position (restores V
2. Connect V
3. Set switches S3 and S6 in the OFF position.
4. Set switches S4 and S5 in the ON position.
5. Set switch 2 in the OUT position (routine is activated).
6. Once PROM dumping is complete, set switch 2 in the RESET
position.
EPROM/OTPROM (PROM)
PP
PP
to V
to V
DD
DD
.
.
PROM Programming Routines
EPROM/OTPROM (PROM)
DD
DD
).
).
Technical Data
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