cp3bt13 National Semiconductor Corporation, cp3bt13 Datasheet - Page 5

• Manufacturer Part Number: cp3bt13
• Description: Cp3bt13 Reprogrammable Connectivity Processor With Bluetooth-r And Can Interfaces
• Manufacturer: National Semiconductor Corporation

3.8
The Triple Clock and Reset module generates a high-speed
main System Clock from an external crystal network. It also
provides the main system reset signal and a power-on reset
function.
This module generates a slow System Clock (32.768 kHz)
from an optional external crystal network. The Slow Clock is
used for operating the device in power-save mode. The
32.768 kHz external crystal network is optional, because
the low speed System Clock can be derived from the high-
speed clock by a prescaler. Also, two independent clocks di-
vided down from the high speed clock are available on out-
put pins.
The Triple Clock and Reset module provides the clock sig-
nals required for the operation of the various CP3BT13 on-
chip modules. From external crystal networks, it generates
the Main Clock, which can be scaled up to 24 MHz from an
external 12 MHz input clock, and a 32.768 kHz secondary
System Clock. The 12 MHz external clock is primarily used
as the reference frequency for the on-chip PLL. Also the
clock for modules which require a fixed clock rate (e.g. the
Bluetooth LLC and the CVSD/PCM transcoder) is generat-
ed through prescalers from the 12 MHz clock. The PLL may
be used to drive the high-speed System Clock through a
prescaler. Alternatively, the high speed System Clock can
be derived directly from the 12 MHz Main Clock.
In addition, this module generates the device reset by using
reset input signals coming from an external reset and vari-
ous on-chip modules.
3.9
The Power Management Module (PMM) improves the effi-
ciency of the device by changing the operating mode and
power consumption to match the required level of activity.
The device can operate in any of four power modes:
T Active—The device operates at full speed using the high-
T Power Save—The device operates at reduced speed us-
T Idle—The device is inactive except for the Power Man-
T Halt—The device is inactive but still retains its internal
3.10
The Multi-Function Timer (MFT) module contains a pair of
16-bit timer/counter registers. Each timer/counter unit can
be configured to operate in any of the following modes:
T Processor-Independent Pulse Width Modulation (PWM)
T Dual Input Capture mode—Measures the elapsed time
T Dual Independent Timer mode—Generates system tim-
frequency clock. All device functions are fully operation-
al.
ing the Slow Clock. The CPU and some modules can
continue to operate at this low speed.
agement Module and Timing and Watchdog Module,
which continue to operate using the Slow Clock.
state (RAM and register contents).
mode—Generates pulses of a specified width and duty
cycle and provides a general-purpose timer/counter.
between occurrences of external event and provides a
general-purpose timer/counter.
ing signals or counts occurrences of external events.
TRIPLE CLOCK AND RESET
POWER MANAGEMENT
MULTI-FUNCTION TIMER
5
T Single Input Capture and Single Timer mode—Provides
3.11
The Versatile Timer Unit (VTU) module contains four inde-
pendent timer subsystems, each operating in either dual 8-
bit PWM configuration, as a single 16-bit PWM timer, or a
16-bit counter with two input capture channels. Each of the
four timer subsystems offer an 8-bit clock prescaler to ac-
commodate a wide range of frequencies.
3.12
The Timing and Watchdog Module (TWM) contains a Real-
Time timer and a Watchdog unit. The Real-Time Clock Tim-
ing function can be used to generate periodic real-time
based system interrupts. The timer output is one of 16 in-
puts to the Multi-Input-Wake-Up module which can be used
to exit from a power-saving mode. The Watchdog unit is de-
signed to detect the application program getting stuck in an
infinite loop resulting in loss of program control or “runaway”
programs. When the watchdog triggers, it resets the device.
The TWM is clocked by the low-speed System Clock.
3.13
The UART supports a wide range of programmable baud
rates and data formats, parity generation, and several error
detection schemes. The baud rate is generated on-chip, un-
der software control.
The UART offers a wake-up condition from the power-save
mode using the Multi-Input Wake-Up module.
3.14
The Microwire/SPI (MWSPI) interface module supports syn-
chronous serial communications with other devices that
conform to Microwire or Serial Peripheral Interface (SPI)
specifications. It supports 8-bit and 16-bit data transfers.
The Microwire interface allows several devices to communi-
cate over a single system consisting of four wires: serial in,
serial out, shift clock, and slave enable. At any given time,
the Microwire interface operates as the master or a slave.
The Microwire interface supports the full set of slave select
for multi-slave implementation.
In master mode, the shift clock is generated on chip under
software control. In slave mode, a wake-up out of power-
save mode is triggered using the Multi-Input Wake-Up mod-
ule.
3.15
The CAN module contains a Full CAN 2.0B class, CAN se-
rial bus interface for applications that require a high-speed
(up to 1Mbits per second) or a low-speed interface with CAN
bus master capability. The data transfer between CAN and
the CPU is established by 15 memory-mapped message
buffers, which can be individually configured as receive or
transmit buffers. An incoming message is filtered by two
masks, one for the first 14 message buffers and another one
for the 15th message buffer to provide a basic CAN path. A
priority decoder allows any buffer to have the highest or low-
est transmit priority. Remote transmission requests can be
processed automatically by automatic reconfiguration to a
receiver after transmission or by automated transmit sched-
one external event counter and one system timer.
VERSATILE TIMER UNIT
TIMING AND WATCHDOG MODULE
UART
MICROWIRE/SPI
CAN INTERFACE
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