Rev. 1.00
178
September 11, 2018
Rev. 1.00
179
September 11, 2018
HT45F4050
A/D NFC Flash MCU
HT45F4050
A/D NFC Flash MCU
• NFCCTRL Register
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
—
STMODEN FCONF1 FCONF0 NFCEN
R/W
—
—
—
—
R/W
R/W
R/W
R/W
POR
—
—
—
—
0
0
0
0
Bit 7~4
Unimplemented, read as "0"
Bit 3
STMODEN
:
Strong modulation mode enable control
0:
Disable
1:
Enable
This bit is used to enhance the field detection ability. If this bit is set high to enable the
strong modulation mode, the available field detected distance will be longer than the
distance when this bit is set low.
Bit 2~1
FCONF1~FCONF0
:
Field detection interrupt trigger condition selection
00:
First State-of-Frame (start of communication) from field off to on
01:
First selection of the tag (active state) from field off to on – NFC tag is in the
ACTIVE state
1x: First field presence – NFC field is present with the HFPON bit set high
These bits are used to select the condition in which the field detection interrupt request
will be triggered. When any condition defined above occurs, the FDF bit in the NFC_
INTF register and the NFCF bit in the INTC3 register will both be set high.
Bit 0
NFCEN
:
NFC function control
0:
Disable
1:
Enable
When this bit is set low, the relevant NFC circuitry will be reset except
for
the NFC
field detector and NFC memory. It is recommended to set this bit high to enable the
NFC function at the beginning of the application program. The NFC function will be
actually enabled when both the NFCEN and HFPON bits are set high.
• NFCWRA Register
Bit
7
6
5
4
3
2
1
0
Name
—
WRA6
WRA5
WRA4
WRA3
WRA2
WRA1
WRA0
R/W
—
R
R
R
R
R
R
R
POR
—
0
0
0
0
0
0
0
Bit 7
Unimplemented, read as "0"
Bit 6~0
WRA6~WRA0
: Last NFC memory page address written by RF
Collisions between the MCU and NFC RF Interface
The NFC memory data can be read from and written to by the
MCU and RF interface. The NFC
memory can be also accessed by the
MCU
even when the RF field is active, however collisions
between the MCU and NFC RF interface as described below may occur and proper protection
mechanism should be enabled to avoid undesired errors.
The activity status of the RF field can be
checked by observing the HFPON bit
.
If
the MCU reads
from or writes
to the NFC memory when the RF interface is writing to the NFC
memory, the hardware should set the WIPF and NFCF bits high and issue an NFC interrupt if the
NFC
E
bit has been set high.
The
MCU must then abort all read
ing
or writ
ing
operations to the NFC
memory.
If
the MCU reads from or writes to the
NFC memory when the RF interface is reading from the
NFC memory, the hardware should set the RIPF and NFCF bits high and issue an NFC interrupt if
the NFC
E
bit has been set high.
The MCU must then abort all read
ing
or writ
ing
operations to the
NFC memory.