CP3BT10 Datasheet, PDF (6/210 Pages) National Semiconductor (TI) – Reprogrammable Connectivity Processor with Bluetooth and USB Interfaces

3.16 ACCESS.BUS INTERFACE
3.18 ADVANCED AUDIO INTERFACE
The ACCESS.bus interface module (ACB) is a two-wire se-
rial interface with the ACCESS.bus physical layer. It is also
compatible with Intel’s System Management Bus (SMBus)
and Philips’ I²C bus. The ACB module can be configured as
a bus master or slave, and can maintain bidirectional com-
munications with both multiple master and slave devices.
The ACCESS.bus receiver can trigger a wake-up condition
out of the low-power modes using the Multi-Input Wake-Up
module.
3.17 DMA CONTROLLER
The Direct Memory Access Controller (DMAC) can speed
up data transfer between memory and I/O devices or be-
tween two memories, relative to data transfers performed di-
rectly by the CPU. A method called cycle-stealing allows the
CPU and the DMAC to use the core bus in parallel. The
DMAC implements four independent DMA channels. DMA
requests from a primary and a secondary source are recog-
nized for each DMA channel, as well as a software DMA re-
quest issued directly by the CPU. Table 1 shows the DMA
channel assignment on the CP3BT10 architecture. The fol-
lowing on-chip modules can assert a DMA request to the
DMAC:
„ CR16C (Software DMA request)
„ USB
„ UART
„ Advanced Audio Interface
„ CVSD/PCM Converter
Table 1 shows how the four DMA channels are assigned
to the modules listed above.
Table 1 DMA Channel Assignment
Channel
Primary/
Secondary
Primary
0
Secondary
Primary
1
Secondary
Primary
2
Secondary
Primary
3
Secondary
Peripheral
USB
UART
UART
Unused
AAI
CVSD/PCM
AAI
CVSD/PCM
Transaction
Read/Write
Read
Write
N/A
Read
Read
Write
Write
The audio interface provides a serial synchronous, full-du-
plex interface to codecs and similar serial devices. Transmit
and receive paths operate asynchronously with respect to
each other. Each path uses three signals for communica-
tion: shift clock, frame synchronization, and data.
In case receive and transmit use separate shift clocks and
frame sync signals, the interface operates in its asynchro-
nous mode. Alternatively, the transmit and receive path can
share the same shift clock and frame sync signals for syn-
chronous mode operation.
The interface can handle data words of either 8- or 16-bit
length and data frames can consist of up to four slots.
In the normal mode of operation, the interface only transfers
one word at a periodic rate. In the network mode, the inter-
face transfers multiple words at a periodic rate. The periodic
rate is also called a data frame and each word within one
frame is called a slot. The beginning of each new data frame
is marked by the frame sync signal.
3.19 CVSD/PCM CONVERSION MODULE
The CVSD/PCM module performs conversion between
CVSD and PCM data, in which the CVSD encoding is as de-
fined in the Bluetooth specification 1.0 and the PCM data
can be 8-bit µ-Law, 8-bit A-Law, or 13-bit to 16-bit Linear.
3.20 SERIAL DEBUG INTERFACE
The Serial Debug Interface module (SDI module) provides
a JTAG-based serial link to an external debugger, for exam-
ple running on a PC. In addition, the SDI module integrates
an on-chip debug module, which allows the user to set up to
four hardware breakpoints on instruction execution and data
transfer. The SDI module can act as a CPU bus master to
access all memory mapped resources, such as RAM and
peripherals. It also provides fast program download into the
on-chip Flash program memory using the JTAG interface.
Note: The SDI module may assert Freeze mode to gather
information, which may cause periodic fluctuations in re-
sponse (bus availability, interrupt latency, etc.). Anomalous
behavior often may be traced to SDI activity.
3.21 DEVELOPMENT SUPPORT
In addition to providing the features needed for the next gen-
eration of embedded Bluetooth products, the CP3BT10 is
backed up by the software resources designers need for
rapid time-to-market, including an operating system, Blue-
tooth protocol stack implementation, peripheral drivers, ref-
erence designs, and an integrated development
environment. Combined with National’s LMX5252 Bluetooth
radio transceiver, the CP3BT10 provides a total Bluetooth
system solution.
National Semiconductor offers a complete and industry-
proven application development environment for CP3BT10
applications, including the IAR Embedded Workbench,
iSYSTEM winIDEA and iC3000 Active Emulator, Bluetooth
Development Board, Bluetooth Protocol Stack, and Applica-
tion Software. See your National Semiconductor sales rep-
resentative for current information on availability and
features of emulation equipment and evaluation boards.
www.national.com
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