ADUC7036DCPZ-RL Analog Devices Inc, ADUC7036DCPZ-RL Datasheet - Page 104

• Manufacturer Part Number: ADUC7036DCPZ-RL
• Description: SFlash 96k ARM7 Dual 16-Bit ADC LIN I.C.
• Manufacturer: Analog Devices Inc
• Series: MicroConverter® ADuC7xxxr

Specifications of ADUC7036DCPZ-RL

• Core Processor: ARM7
• Core Size: 16/32-Bit
• Speed: 20.48MHz
• Connectivity: LIN, SPI, UART/USART
• Peripherals: PSM, Temp Sensor, WDT
• Number Of I /o: 9
• Program Memory Size: 96KB (96K x 8)
• Program Memory Type: FLASH
• Eeprom Size: -
• 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 ~ 115°C
• Package / Case: 48-VFQFN Exposed Pad, CSP
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

ADuC7036
UART SERIAL INTERFACE
The ADuC7036 features a 16,450-compatible UART. The UART
is a full-duplex, universal, asynchronous receiver/transmitter. A
UART performs serial-to-parallel conversion on data characters
received from a peripheral device and performs parallel-to-serial
conversion on data characters received from the ARM7TDMI.
The UART features a fractional divider that facilitates high accu-
racy baud rate generation and a network addressable mode. The
UART functionality is available on the GPIO_5/IRQ1/RxD and
GPIO_6/ TxD pins of the ADuC7036.
The serial communication adopts an asynchronous protocol that
supports various word lengths, stop bits, and parity generation
options selectable in the configuration register.
BAUD RATE GENERATION
The ADuC7036 features two methods of generating the UART
baud rate: normal 450 UART baud rate generation and ADuC7036
fractional divider baud rate generation.
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 (each is a 16-bit
value, DL). The standard baud rate generator formula is
Table 79 lists common baud rate values.
Table 79. Baud Rate Using the Standard Baud Rate Generator
Baud Rate (bps)
9600
19,200
115,200
9600
19,200
115,200
Baud
Rate
=
2
CD
CD
0
0
0
3
3
3
20
×
.
48
16
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. C | Page 104 of 132
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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 is as follows:
where:
CD is the clock divider.
DL is the divisor latch.
M is the integer part of the divisor; a fractional divider divides
an input by a nonwhole number, M.N.
N is the fractional part of the divisor; a fractional divider
divides an input by a nonwhole number, M.N.
Table 80 lists common baud rate values.
Table 80. Baud Rate Using the Fractional Baud Rate Generator
Baud Rate
(bps)
9600
19,200
115,200
Baud
M
+
CLOCK
CORE
2048
Figure 43. Fractional Divider Baud Rate Generation
Rate
N
CD
0
0
0
=
=
/(M+N/2048)
Baud
2
CD
DL
0x42
0x21
0x5
/2
×
Rate
16
×
20
20
DL
×
M
1
1
1
.
FBEN
48
.
2
48
CD
×
MHz
2
MHz
N
21
×
21
228
×
(
16
M
/16DL
×
+
DL
Actual
Baud Rate
9598.55
19,197.09
115,177.51
2048
N
×
2
)
UART
% Error
0.015%
0.015%
0.0195%
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