MC68HC705V12CFN MOTOROLA [Motorola, Inc], MC68HC705V12CFN Datasheet - Page 122

• Manufacturer Part Number: MC68HC705V12CFN
• Description: The Motorola microcontroller
• Manufacturer: MOTOROLA [Motorola, Inc]

EPROM and EEPROM
12.3 EPROM Bootloader
12.4 Bootloader Functions
Advance Information
122
Bootloader programming mode is entered upon the rising edge of
RESET if the IRQ/V
bootloader code resides in the ROM from $3C00 to $3FEF. This
program handles copying of user code from an external EPROM into the
on-chip EPROM.
The user code must be a one-to-one correspondence with the internal
EPROM addresses (including the mask option register (MOR)).
Three pins are used to select various bootloader functions. These pins
are PD2, PD1, and PD0. PD3 and PD4 are tied to logic 0. Two other
pins, PA6 and PA5, are used to drive the PROG LED and the VERF
LED, respectively. The programming modes are shown in
PD2
0
0
0
0
1
1
EPROM and EEPROM
Table 12-1. Bootloader Functions
PP
PD1
0
0
1
1
0
0
pin is at V
PD0
0
1
0
1
0
1
TST
and the PA6 pin is at logic 1. The
Program/verify EPROM
Verify only
Factory use
Jump to top of EEPROM
Jump to top of RAM
Jump to top of EPROM
MC68HC705V12
Mode
Table
MOTOROLA
—
Rev. 3.0
12-1.