LMX5001VBC NSC [National Semiconductor], LMX5001VBC Datasheet - Page 9

• Manufacturer Part Number: LMX5001VBC
• Description: Dedicated Bluetooth Link Controller
• Manufacturer: NSC [National Semiconductor]

Byte No.
Byte 0
Byte 1
Byte 2
Byte No.
Byte 0
Byte 1
Byte 2
Functional Description
STATUS DATA — Byte 0
Bytes 0 contains LMX5001 version number. It is in
STATUS DATA — Byte 1
Bytes 1 contains GPIO input value. There are no corre-
sponding enable bits for these GPIOs.
STATUS DATA — Byte 2 and 3
Bytes 2 and 3 contain maximum correlation value of the re-
ceiving package. This value is 10-bit in length with Byte 2
containing the least significant byte and the lower 2 bits of
Byte 3 containing the remaining 2 most significant bits (refer-
ence Table 3 ).
STATUS DATA — Byte 4 and 5
Bytes 4 and 5 contain timeskew value. A timeskew is the
phase difference between master and slave clock. The fol-
lowing formula is used to calculate timeskew: timeskew =
slave clock - master clock.
Timeskew is within the range of −2499 to 2499. Its value is in
125 ns. That represents a clock value ranging −312.5 µs to
312.5 µs.
Note from Table 4 , that bit 6 of Byte 0 (CORR) contains an
Access Code correlation status bit. When this bit is logic “0”
this indicates to the Link Management Controller that a sat-
isfactory level of correlation exists between the incoming
data packet’s Access Code and the Bluetooth Access Code
present in the LMX5001. It follows that a logic “1” indicates
that the received data packet’s Access Code did not suffi-
ciently match that contained in the LMX5001.
The 4 Trailer bits (in Byte 0 and 1 above) are the Trailer bit
which immediately follow the Sync Word on which an Access
Code correlation has just be done. Note that the bit “Trail(0)”
is disregarded in most situations, due to the fact that the bit
timing is also being obtained from the correlation task (this
being updated in most cases).
Note from Table 5 , that, following the first two bits (which are
ignored by the LMX5001), the subsequent 16 bits contain an
“Extended Preamble”. While this is not a requirement of the
Bluetooth Specification, they are included to improve Radio
performance.
Following Byte 2, subsequent Bytes presented to the
LMX5001 LCI should contain the data which is to be trans-
mitted over the Bluetooth link. The format for this data should
<
Major
>
.
<
Minor
Extpre(14)
Extpre(6)
head(6)
Bit 7
trail(2)
Bit 7
>
X
0
format.
Extpre(1‘5)
Extpre(7)
head(7)
CORR
trail(3)
Bit 6
Bit 6
X
(Continued)
TABLE 5. LCI — Bluetooth Transmit Data
TABLE 4. LCI — Bluetooth Receive Data
head(0)
head(8)
Extpre(0)
Extpre(8)
Bit 5
Pre(0)
Bit 5
0
head(1)
head(9)
Extpre(1)
Extpre(9)
Bit 4
Pre(1)
Bit 4
0
9
Timeskew is 13-bit in length with Byte 4 containing the least
significant byte and the lower 5 bits of Byte 5 containing the
remaining 5 most significant bits (reference Table 3 ).
STATUS DATA — Byte 6 through 9
Bytes 6 through 9 contain the value of the native clock in half
Bluetooth slot, 312.5 µs. This value is 28-bit in length with
Byte 6 through 8 containing the least significant 3 bytes and
the lower 4 bits of Byte 9 containing the 4 most significant
bits (reference Table 3 ).
STATUS DATA — Byte 10
Bytes 10 contains RSSI AD value from the LMX3162 Radio
Controller. This value is 5 bits in length occupying the lower
5 bits.
BLUETOOTH RECEIVE DATA
Bluetooth Receive Data is passed to the Link Management
Controller via the LCI, using RxData in conjunction with
RxFrSync and SCLK. Receive Data is formatted into 3, 8-bit
Bytes (reference Table 4 ).
Bluetooth Receive Data will continuously be presented to the
LCI whenever the LMX5001 is executing “Slave Receive
with Windowed Correlation” or “Master Receive” (reference
LMX5001 Command Set). However, when a “Slave Receive
with Continuous Correlation” is executed, Receive Data will
only be present on the LCI when its Access Code correlation
exceeds the AC Threshold (reference “Access Code Corre-
lation” section of this Datasheet).
BLUETOOTH TRANSMIT DATA
Bluetooth Transmit Data is received by the LMX5001, from
the Link Management Controller via the LCI, using TxData in
conjunction with TxFrSync and SCLK. Transmit Data is for-
matted as follows (reference Table 5 ):
follow the convention laid out above. Once the data has
been forwarded to the LMX5001, the Transmit mode is ex-
ited by the Link Management Controller asserting a SYS-
LOAD on the LCI.
Extpre(10)
head(10)
Extpre(2)
head(2)
Bit 3
Pre(2)
Bit 3
0
Extpre(11)
head(11)
Extpre(3)
head(3)
Pre(0)
Bit 2
Bit 2
0
Extpre(12)
head(12)
Extpre(4)
head(4)
Sync(0)
trail(0)
Bit 1
Bit 1
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Extpre(13)
head(13)
Extpre(5)
head(5)
Sync(1)
trail(1)
Bit 0
Bit 0