ADUC7129BSTZ126-RL Analog Devices Inc, ADUC7129BSTZ126-RL Datasheet - Page 53

• Manufacturer Part Number: ADUC7129BSTZ126-RL
• Description: IC DAS MCU ARM7 ADC/DDS 80-LQFP
• Manufacturer: Analog Devices Inc
• Series: MicroConverter® ADuC7xxxr

Specifications of ADUC7129BSTZ126-RL

• Core Size: 16/32-Bit
• Program Memory Size: 126KB (126K x 8)
• Core Processor: ARM7
• Speed: 41.78MHz
• Connectivity: EBI/EMI, I²C, SPI, UART/USART
• Peripherals: PLA, POR, PWM, PSM, Temp Sensor, WDT
• Number Of I /o: 38
• Program Memory Type: FLASH
• Ram Size: 8K x 8
• Voltage - Supply (vcc/vdd): 3 V ~ 3.6 V
• Data Converters: A/D 10x12b; D/A 1x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 125°C
• Package / Case: 80-LQFP
• Controller Family/series: (ARM7) ADUC
• No. Of I/o's: 40
• Cpu Speed: 41.78MHz
• No. Of Timers: 5
• Digital Ic Case Style: LQFP
• Embedded Interface Type: I2C, SPI, UART
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant
• Other names: ADUC7129BSTZ126-RLTR

Table 67. PWMCON2 MMR Bit Designations
Bit
7
6:4
3:0
When calculating the time from the convert start delay to the
start of an ADC conversion, the user needs to take account of
internal delays. The example below shows the case for a delay of
four clocks. One additional clock is required to pass the convert
start signal to the ADC logic. Once the ADC logic receives the
convert start signal an ADC conversion begins on the next
ADC clock edge (see Figure 50).
SIGNAL PASSED
TO ADC LOGIC
PWM SIGNAL
TO CONVST
Value
0000
0001
0010
0011
0100
0101
0110
0111
1000
1001
1010
1011
1100
1101
1110
1111
LOW SIDE
UCLOCK
COUNT
Name
CSEN
RSVD
CSD3
CSD2
CSD1
CSD0
Figure 50. ADC Conversion
Description
Set to 1 by the user to enable the PWM
to generate a convert start signal.
Cleared by user to disable the PWM
convert start signal.
Reserved. This bit should be set to 0 by
the user.
Convert Start Delay. Delays the convert
start signal by a number of clock pulses.
4 clock pulses.
8 clock pulses.
12 clock pulses.
16 clock pulses.
20 clock pulses.
24 clock pulses.
28 clock pulses.
32 clock pulses.
36 clock pulses.
40 clock pulses.
44 clock pulses.
48 clock pulses.
52 clock pulses.
56 clock pulses.
60 clock pulses.
64 clock pulses.
Rev. 0 | Page 53 of 92
Quadrature Encoder
A quadrature encoder is used to determine both the speed and
direction of a rotating shaft. In its most common form, there are
two digital outputs, S1 and S2. As the shaft rotates, both S1 and
S2 toggle; however, they are 90° out of phase. The leading output
determines the direction of rotation. The time between each
transition indicates the speed of rotation.
The quadrature encoder takes the incremental input shown in
Figure 51 and increments or decrements a counter depending
on the direction and speed of the rotating shaft.
On the ADuC7128/ADuC7129, the internal counter is clocked
on the rising edge of the S1 input, and the S2 input indicates the
direction of rotation/count. The counter increments when S2
is high and decrements when it is low.
In addition, if the software has prior knowledge of the direction
of rotation, one input can be ignored (S2) and the other can act
as a clock (S1).
For additional flexibility, all inputs can be internally inverted
prior to use.
The quadrature encoder operates asynchronously from the
system clock.
Input Filtering
Filtering can be applied to the S1 input by setting the FILTEN
bit in QENCON. S1 normally acts as the clock to the counter;
however, the filter can be used to ignore positive edges on S1
unless there has been a high or a low pulse on S2 between two
positive edges on S1 (see Figure 52).
S2 HIGH PULSE
S2 LOW PULSE
CLOCKWISE
S1
Figure 51. Quadrate Encoder Input Values
S1
Figure 52. S1 Input Filtering
00
01
11
10
00
01
11
10
00
01
11
10
00
ADuC7128/ADuC7129
S2
COUNTER CLOCKWISE