ADUC7032BSTZ-8L-RL Analog Devices Inc, ADUC7032BSTZ-8L-RL Datasheet - Page 95

• Manufacturer Part Number: ADUC7032BSTZ-8L-RL
• Description: IC,Battery Management,QFP,48PIN,PLASTIC
• Manufacturer: Analog Devices Inc
• Series: MicroConverter® ADuC7xxxr

Specifications of ADUC7032BSTZ-8L-RL

• Core Processor: ARM7
• Core Size: 16/32-Bit
• Speed: 20.48MHz
• Connectivity: LIN, SPI, UART/USART
• Peripherals: POR, PSM, Temp Sensor, WDT
• Number Of I /o: 9
• Program Memory Size: 96KB (96K x 8)
• Program Memory Type: FLASH
• Ram Size: 6K x 8
• Voltage - Supply (vcc/vdd): 3.5 V ~ 18 V
• Data Converters: A/D 2x16b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 105°C
• Package / Case: 48-LQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Lead Free Status / Rohs Status: Compliant

UART SERIAL INTERFACE
The ADuC7032-8L features a 16,450-compatible UART. The
UART is a full-duplex universal asynchronous receiver/
transmitter that performs serial-to-parallel conversion on data
characters received from a peripheral device or a modem, and
parallel-to-serial conversion on data characters received from
the ARM7TDMI. The UART features a fractional divider, which
facilitates high accuracy baud rate generation, and a network
addressable mode. The UART functionality is made available on
GPIO_5 and GPIO_6 (RxD and TxD) of the ADuC7032-8L.
The serial communication adopts an asynchronous protocol
that supports various word length, stop bits, and parity
generation options selectable in the configuration register.
BAUD RATE GENERATION
The ADuC7032-8L features two methods of generating the
UART baud rate.
•
•
These two methods are explained in detail in the Normal 450
UART Baud Rate Generation section and the ADuC7032-8L
Fractional Divider section.
Normal 450 UART Baud Rate Generation
The baud rate is a divided version of the core clock using the
value in COMDIV0 and COMDIV1 MMRs (16-bit value, DL).
Table 79 lists common baud rate values.
Table 79. Baud Rate Using the Standard Baud Rate Generator
Baud Rate
9600
19,200
115,200
9600
19,200
115,200
Normal 450 UART baud rate generation
ADuC7032-8L fractional divider
Bau
d
Rate
CD
0
0
0
3
3
3
=
2
CD
20
×
.
16
48
DL
0x43
0x21
0x6
0x8
0x4
0x1
×
MHz
2
×
DL
Actual
Baud Rate
9552
19,394
106,667
10,000
20,000
80,000
% Error
0.50
1.01
7.41
4.17
4.17
30.56
Rev.0 | Page 95 of 116
ADuC7032-8L Fractional Divider
The fractional divider combined with the normal baud rate
generator allows the generation of accurate, high speed baud rates.
Calculation of the baud rate using a fractional divider follows:
Table 80 shows some common baud rate values.
Table 80. Baud Rate Using the Fractional Baud Rate Generator
Baud
Rate
9600
19,200
115,200
UART REGISTER DEFINITIONS
The UART interface consists of the following 10 registers:
•
•
•
•
•
•
•
•
•
•
COMTX, COMRX, and COMDIV0 share the same address
location. COMTX and COMRX can be accessed when Bit 7 in
the COMCON0 register is cleared. COMDIV0 can be accessed
when Bit 7 of COMCON0 is set.
COMTX: 8-bit transmit register
COMRX: 8-bit receive register
COMDIV0: divisor latch (low byte)
COMDIV1: divisor latch (high byte)
COMCON0: line control register
COMCON1: UART control register
COMSTA0: line status register
COMIEN0: interrupt enable register
COMIID0: interrupt identification register
COMDIV2: 16-bit fractional baud divide register
Baud
M
+
CLOCK
CORE
2048
Figure 37. Fractional Divider Baud Rate Generation
Rate
N
CD
0
0
0
=
=
/(M+N/2048)
Baud
DL
0x42
0x21
0x5
2
CD
/2
×
16
Rate
M
1
1
1
×
20
20
DL
×
FBEN
.
48
N
21
21
228
.
2
48
×
CD
MHz
2
MHz
×
×
16
(
Actual
Baud Rate
9598.55
19,197.09
115,177.51
M
/16DL
×
+
DL
ADuC7032-8L
2048
×
N
2
UART
)
% Error
0.015
0.015
0.0195