Peripheral Simulation
For STMicroelectronics STR755FV2 — Analog/Digital Converter (ADC)
Simulation support for this peripheral or feature is comprised of:
- Dialog boxes which display and allow you to change peripheral configuration.
- VTREGs (Virtual Target Registers) which support I/O with the peripheral.
These simulation capabilities are described below.
Analog / Digital Converter Dialog
The Analog / Digital Converter dialog displays and configures
the A/D converter. The controls in this dialog are separated into
several logical groups.
Control and Status
-
ADC_CSR (ADC Control & Status Register)
contains the following control and status settings:
-
A (Channel Address) selects the channel to be
sampled when external addressing (AXT) is enabled.
-
OR (Overrun) is set when one of the data channels is
overwritten before being read.
-
AXT (Addressing External Enable) is set to allow
single-channel conversion. If reset, channels are addressed in a
round-robin fashion.
-
IEn (Interrupt Enable - Channel n) is
set to enable interrupts for the corresponding channel
n.
-
DAn (Data Available - Channel n) is
set when new sample data is ready to be read for channel
n.
Prescaler
-
ADC_CPR (ADC Prescaler Register) contains the following
prescaler settings:
-
PRESC (Prescaler Value) is the 12-bit PCLK2 clock
divisor used to produce the oversampling clock.
-
Fmod(Hz) (Modulator Oversampling Frequency) is the
sampling frequency input to the ADC.
-
Rate(Hz) (Modulator Oversampling Rate) is oversampling
rate based on the prescaling factor (PRESC).
Data
-
ADC_DATAn (ADC Data Register) contains the raw
converted result of the ADC conversion for channel n.
-
DATAn (Converted Data) contains the converted
data value for channel n.
Analog Inputs
-
AINn (Analog Input) contains the simulated
analog input voltage (VTREG AINn) for channel
n.
Reference & Center
-
VREF is the feedback reference voltage used for the
ADC.
-
VCM is the midpoint between the voltage range of the ADC
converter and the feedback reference voltage (VREF).
AINx Input Voltage VTREG
Data Type: float
The AINx VTREGs set the analog input voltages for simulated A/D
converters. The AINx VTREGs represent the inputs to the analog input
pins of the MCU for analog input 0, 1, 2, and so on. AIN0 sets the
input voltage for analog input #0, AIN1 sets the input voltage for
analog input #1, etc. If you have properly configured the analog
inputs, the following commands (typed in the debugger's Command
Window) input the voltages specified.
AIN0 = 0.000 /* Analog Input 0 = 0.000 volts */
AIN1 = 2.500 /* Analog Input 1 = 2.500 volts */
AIN2 = 4.999 /* Analog Input 2 = 4.999 volts */
You may create a debugger signal function to periodically change
the value of the A/D input. The following signal function increases
the A/D Channel 1 input voltage by 0.1 volts each second.
signal void AIN1_sig (void) {
float f;
for (f = 0.0; f < 5.0; f += 0.1)
{
swatch (1.0); // Delay 1 second
AIN1 = f; // Set AIN1 Voltage
}
}
VREF Voltage VTREG
Data Type: unsigned short