MC68HC711K4CFN4 Datasheet, PDF (19/80 Pages) Motorola, Inc – 8-Bit Microcontroller

6. Clear the EPROG register to reconfigure the EPROM address and data buses for normal op-
eration.
In EPROM emulation mode (PROG mode), the EPROM/OTPROM is programmed as a stand-alone
EPROM by adapting the MCU footprint to the 27C256-type EPROM and using an appropriate EPROM
programmer. To put the MCU in PROG mode, pull the following pins low: MODA/LIR, MODB/V_STBY,
RESET, PA[2:0]. Refer to Figure 6.
In the third 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 pro-
gramming utility can be used. To use the resident utility, bootload a three-byte program consisting of a
single jump instruction to $BF00. $BF00 is the starting address of a resident EPROM programming util-
ity. The utility program sets the X and Y index registers to default values, then receives programming
data from an external host and programs it into 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 = $A000).
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 corre-
sponding verification data is returned, the programming operation is terminated by resetting the MCU.
Although the external 12.25 V programming voltage must be applied to the XIRQ/V_PPE pin during
EPROM programming, it should be equal to V_DD before verifying the data that was just programmed. It
should equal V_DD during normal operation also. The XIRQ/V_PPE pin has a high voltage detect circuit
that inhibits assertion of the ELAT bit when programming voltage is at low levels.
CAUTION
If the MCU is used in any operating mode while high voltage (12.25 V nominal) is
present on the XIRQ/V_PPE pin, the IRQ/CE pin must be pulled high to avoid acci-
dental programming or corruption of EPROM contents. After programming an
EPROM location, IRQ pin must also be pulled high before the address and data
are changed to program the next location.
EPROG — EPROM Programming Control
$002B
RESET:
Bit 7
MBE
0
6
5
4
3
2
—
ELAT EXCOL EXROW
—
0
0
0
0
0
1
Bit 0
—
EPGM
0
0
MBE —Multiple-Byte Programming Enable
0 = EPROM array configured for normal programming
1 = Program two bytes with the same data
When multiple-byte programming is enabled, address bit 5 is considered a don't care so that bytes with
address bit 5 = 0 and address bit 5 = 1 both get programmed. MBE can be read in any mode and always
reads zero in normal modes. MBE can only be written in special modes.
Bit 6 —Not implemented
Always reads zero
ELAT —EPROM Latch Control
ELAT can be read any time. ELAT can be written any time except when EPGM = 1, then the write to
ELAT will be disabled. When ELAT = 1, writes to EPROM cause address and data to be latched and
the EPROM cannot be read.
0 = EPROM address and data bus configured for normal reads
1 = EPROM address and data bus configured for programming
M68HC11 K Series
MC6HC11KTS/D
MOTOROLA
19