ADC and DAC

Started by sherifkamelzaki in LPC200013 years ago 3 replies

hi i am using LPC2138 and my application is related to voice something like storing the voice for 4 s then playing it back i test the adc...

hi i am using LPC2138 and my application is related to voice something like storing the voice for 4 s then playing it back i test the adc and Dac after each other it worked but when i try to store the values of the ADc to resend them later to the DAC but the output sounded lick tic tic tic thank you


ADC Test Setting

Started by peterburdine in LPC200014 years ago 1 reply

Can anyone please explain the test settings for the ADC on the LPC2xxx? 00=Normal Mode - Ok, I know this one 01=Digital Test Mode -...

Can anyone please explain the test settings for the ADC on the LPC2xxx? 00=Normal Mode - Ok, I know this one 01=Digital Test Mode - Does this mean that you set the output of the pin to be 1 or 0 and then read 0x3FF or 0x000 from the ADC? 10=DAC Test Mode - ? 11=Simple Conversion Test Mode - ? Thanks, Peter


DAC/ADC Sampling frequency

Started by omprakash alone in LPC20008 years ago 1 reply

hi, I am using LPC2148 ARM controller having 2- ADC (6+8 Channels) with sampling frequency 410 ksps and 1-DAC with 400 ksps. but i want to modify...

hi, I am using LPC2148 ARM controller having 2- ADC (6+8 Channels) with sampling frequency 410 ksps and 1-DAC with 400 ksps. but i want to modify the sampling frequency of ADC/DAC according to my requirements say 50 Hz. For that let me know what i have to do? Again, i wnat to use two channels of ADC, I have done it for one channel, if i want to use another channel, then what chnages i have ...


adc - simple adc sample doesn't work

Started by klemen_dovrtel in LPC200011 years ago 10 replies
ADC

I tested a simple adc conversion example, but it doesn't work. The adc conversion never ends. It gets stuck in the while loop waiting for...

I tested a simple adc conversion example, but it doesn't work. The adc conversion never ends. It gets stuck in the while loop waiting for A/D conversion to end. I added a simple debug message to get the regVal value in the while loop - regVal=0x00010008. Any idea what could be wrong? #define ADC_OFFSET 0x10 #define ADC_INDEX 4 #define ADC_DONE 0x80000000 #define ADC_OVERRUN 0x40000000 ...


LPCUSB + usbISR + external IRQ = no cyclic readout

Started by CeDeROM in LPC200010 years ago 4 replies

Hello world! :-) I have this little problem, that I dont really know how/if can be solved - its about interrupts generated every 1ms by the...

Hello world! :-) I have this little problem, that I dont really know how/if can be solved - its about interrupts generated every 1ms by the USB Host to my LPC2148 based device. These requests break my cyclic ADC readouts causing serious sample loss. ADC is connected to EINT and have priority 1 (0 is for Timer0 used by FreeRTOS). ADC signal complete acquisition by generating higt-to-low ...


LPC2132/01 ADC issue

Started by gmpundlik in LPC20009 years ago 7 replies

Hello all, I am using the LPC2132 (with enhanced ADC) for reading a hall-effect potentiometer, operated on 5V. I have used a instrumentation...

Hello all, I am using the LPC2132 (with enhanced ADC) for reading a hall-effect potentiometer, operated on 5V. I have used a instrumentation amplifier AD8226 to amplify and shift the output so that the usable range comes within 0.5~3V The digital value varies each time I read the same potentiometer output. The variation is random and spans over 100~125 counts of the ADC output. That is more ...


LPC2138 ADC problem

Started by hus_kalydonios in LPC200011 years ago 4 replies

Hi all, I'm trying to test the ADC on the LPC2138 (using Rowley and Olimex evaluation board), but I can't get it to work and I can't figure...

Hi all, I'm trying to test the ADC on the LPC2138 (using Rowley and Olimex evaluation board), but I can't get it to work and I can't figure it out. The ADC conversion never completes and my code just blocks while waiting for the done bit to be set... Here's my code: //init //#define AD0CR (*((volatile unsigned long *) 0xE0034000)) //#define AD0DR (*((volatile u...


LPC2888 interfacing with ADC.

Started by Prashant A in LPC20009 years ago 1 reply

Hi, I am facing a strange problem here. When i configure the LCD pins as input, and connect a 10 bit ADC to the same, the processor...

Hi, I am facing a strange problem here. When i configure the LCD pins as input, and connect a 10 bit ADC to the same, the processor simply hangs. This is because i have a statement as soon as you enter main, setting a port pin for LED to glow. But when i connect the ADC and then power it on, the LED fails to glow. Can anyone help me out. Any input would be appreciate...


Error in LPC213x users manual

Started by rggmns in LPC200013 years ago 2 replies

Hello, I have spend some time in getting the ADC on the move. The users manual states on page 198 that the ADC inputs are always ...

Hello, I have spend some time in getting the ADC on the move. The users manual states on page 198 that the ADC inputs are always connected to the I/O pins of the LPC. This is NOT correct. You DO HAVE TO use the PINSEL registers to connect the ADC inputs with the I/O connections. My users manual is release November 22 2004. If there is a more recent


LPC2138 ADC Question

Started by fitzdean in LPC200011 years ago 9 replies

We are having strange behavior with our ADC code. In many of the examples I have seen in this forum, there seems to be a strong trend toward the...

We are having strange behavior with our ADC code. In many of the examples I have seen in this forum, there seems to be a strong trend toward the following sequence of events: *PCONP and PINSELx properly set up *ADC control register written to with everything set up but conversion not started *Start conversion bit or'd into the control register. *Wait for DONE *When DONE received, cle...


ADC reference voltage

Started by tasking12 in LPC200014 years ago 1 reply

Hi all, does anyone know has ADC of LPC210x a one internal reference or use analog 3.3V as reference. In other words is the ADC...

Hi all, does anyone know has ADC of LPC210x a one internal reference or use analog 3.3V as reference. In other words is the ADC result depend on effektiv voltage on the analog 3.3V pad? Thanks


ADC interrupt code

Started by sherifkamelzaki in LPC200013 years ago

Hi how are u all please i need some help here my code uses the ADC to enter the interrupt it doesn't work #include static int...

Hi how are u all please i need some help here my code uses the ADC to enter the interrupt it doesn't work #include static int timer0Count, timer1Count; void init_ADC(void) { PINSEL0 |= 0x00000300; // select pin0.4 as AD pin AD0.6 PCONP |= 0x00001000; // enable the power to ADC.0 AD0CR = 0x00214040; // configure the AD & run at 88Khz clk at


Re: LPC2138 ADC missed samples when using external trigger

Started by sig5...@hotmail.com in LPC200011 years ago 1 reply

I did a design with the LPC2138 and used heavy ADC. But don't think I used any ext trigger to activate ADC. But I used other ext ints. There...

I did a design with the LPC2138 and used heavy ADC. But don't think I used any ext trigger to activate ADC. But I used other ext ints. There are many issues that could be involved in your problem, including what the INT service routine is doing. I would recommend you set some various traps/breakpoints and try to narrow down the cause. INTs all have a priority. Depending on how you have setu...


using LPC2148 ADC in power down mode

Started by Mohamad Tayssir Alkowatly in LPC20009 years ago 1 reply

Hi all I've come across a paper where they use ADC in power down mode on some microchip MCU not to reduce power consumption but to lower the...

Hi all I've come across a paper where they use ADC in power down mode on some microchip MCU not to reduce power consumption but to lower the noise caused by the MCU operation. First, when this sounds logical, how much does is really improve the ADC operation accuracy ? Second, I've tried to do this by setting the PDN bit to zero in the ADCR register instead of one when requesting the ...


Problem with ADC

Started by shakeel_qau in LPC200010 years ago 3 replies
ADC

Hi i am using lpc2368,with ADS v1.2 ,i am facing problem with A to D conversions.i get the right values in ADC for given analog input if i...

Hi i am using lpc2368,with ADS v1.2 ,i am facing problem with A to D conversions.i get the right values in ADC for given analog input if i use VREF 3.3v ,as soon as i change reference to 1.2v the values i read from ADC are not correct for given analog input even at 0v input,plz help Shakeel ------------------------------------


ADC Issue

Started by Jerry in LPC20007 years ago 72 replies
ADC

I'm seeing an intermittent problem when reading the ADC on an LPC1768. I'm reading ADC channel 1 in software-start mode and 99% of the time I'm...

I'm seeing an intermittent problem when reading the ADC on an LPC1768. I'm reading ADC channel 1 in software-start mode and 99% of the time I'm seeing results within range. For this test, I'm reading a voltage divider that divides the 3.3v reference by 2, so I'm expecting to see something in the 2048 range, which I do 99% of the time. Occasionally, I see 4095 returned when I read channel 1. I h...


LPC1763 ADC Burst mode with interrupts

Started by robertfleury in LPC20007 years ago

Hi all, Im trying to get the ADC working reliably on my LPC1763 board under crossworks. Some interesting behaviour I noticed but would...

Hi all, Im trying to get the ADC working reliably on my LPC1763 board under crossworks. Some interesting behaviour I noticed but would like some confirmation on. My basic implementation is a Timer ISR which sets burst mode active, and an ADC interrupt that is triggered on a set channel where i first disable burst mode and then read the data from the registers. Currently, I have my ...


Re: ADC Issue

Started by Jerry in LPC20006 years ago 1 reply

--- In l...@yahoogroups.com, "Jerry" wrote: > > --- In l...@yahoogroups.com, "Chris" wrote: > > Now if I don't have the code setup...

--- In l...@yahoogroups.com, "Jerry" wrote: > > --- In l...@yahoogroups.com, "Chris" wrote: > > Now if I don't have the code setup right, I can get totally wild readings back from the ADC. > > I would suggest you try different ADC code and see what happens. Here's an update to my original posting from several months ago.. In that original post, I asked about the seem


LPC2000 automotive ADC vs MAC7100

Started by ualbe in LPC200013 years ago 2 replies

Dear LPC Group, i'm starting to develope an automotive project with ADC. has someone experience on LPC ADC module? My vendor has...

Dear LPC Group, i'm starting to develope an automotive project with ADC. has someone experience on LPC ADC module? My vendor has unsuggested me to use LPC on automotive project, he suggest me to use MAC7100. What about? Alberto Ubertelli


ADC Problem

Started by heedaf in LPC200013 years ago 1 reply
ADC

I've got the following code to start the ADC. If I put in a breakpoint somewhere after the code and run to the breakpoint it will enter an...

I've got the following code to start the ADC. If I put in a breakpoint somewhere after the code and run to the breakpoint it will enter an endless loop. If I step manually past the while statement and than run to the breakpoint it will work fine. If I put in a delay before the while statement it also works but this seriously slows down the ADC. I guess this has something to do with i...