Operating Modes and On-Chip Memory
Data Sheet
M68HC11E Family — Rev. 5
54
Operating Modes and On-Chip Memory
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MOTOROLA
2.4.2 Programming the EPROM with Downloaded Data
When using this method, the EPROM is programmed by software while in the
special test or bootstrap modes. User-developed software can be uploaded
through the SCI or a ROM-resident EPROM programming utility can be used. The
12-volt nominal programming voltage must be present on the XIRQ/V
PPE
pin. To
use the resident utility, bootload a 3-byte program consisting of a single jump
instruction to $BF00. $BF00 is the starting address of a resident EPROM
programming utility. The utility program sets the X and Y index registers to default
values, then receives programming data from an external host, and puts it in
EPROM. The value in IX determines programming delay time. The value in IY is a
pointer to the first address in EPROM to be programmed (default = $D000).
When the utility program is ready to receive programming data, it sends the host
the $FF character. Then it waits. When the host sees the $FF character, the
EPROM programming data is sent, starting with the first location in the EPROM
array. After the last byte to be programmed is sent and the corresponding
verification data is returned, the programming operation is terminated by resetting
the MCU.
For more information, Motorola application note AN1060 entitled
M68HC11
Bootstrap Mode
has been included at the back of this document.
2.4.3 EPROM and EEPROM Programming Control Register
The EPROM and EEPROM programming control register (PPROG) enables the
EPROM programming voltage and controls the latching of data to be programmed.
For MC68HC711E9, PPROG is also the EEPROM programming control
register.
For the MC68HC711E20, EPROM programming is controlled by the
EPROG register and EEPROM programming is controlled by the PPROG
register.
ODD — Program Odd Rows in Half of EEPROM (Test) Bit
Refer to
2.5 EEPROM
.
EVEN — Program Even Rows in Half of EEPROM (Test) Bit
Refer to
2.5 EEPROM
.
Address: $103B
Bit 7
6
5
4
3
2
1
Bit 0
Read:
ODD
EVEN
ELAT
(1)
BYTE
ROW
ERASE
EELAT
EPGM
Write:
Reset:
0
0
0
0
0
0
0
0
1. MC68HC711E9 only
Figure 2-14. EPROM and EEPROM Programming
Control Register (PPROG)
F
Freescale Semiconductor, Inc.
n
.