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lucid analog input tutorial problem - caravandal - 05-11-2020

when i run the tutorial code to send multiple pots to pwm  i only get 4 displayed at any one time. then when i push the rst button it swaps tothe other 4. can someone point out whats making this happen and maybe help me get all 8 dispayed at the same time...


RE: lucid analog input tutorial problem - alchitry - 05-11-2020

This doesn't make a whole lot of sense why that would happen. Could you share your code?

I'm assuming this is for the Mojo?


RE: lucid analog input tutorial problem - caravandal - 05-19-2020

hi. sorry for the delay. after some more testing i now realise the mojo behaves as it should when powered from the usb connector. but when powered from a 12v psu to the barrel connector it only shows 4 leds at a time (every other one) then swaps to the other 4 when i press reset. the code is straight out of the tutorial...

module adc_to_leds (
input clk, // clock
input rst, // reset
output channel[4], // channel we want to sample
input sample[10], // sample value
input sample_channel[4], // channel the sample is from
input new_sample, // 1 = new sample
output leds[8] // output to leds
) {

// This is used to convert 0 to 7 to its corresponding channel 0 to 1 and 4 to 9
const LED_TO_CHANNEL = {4d9,4d8,4d7,4d6,4d5,4d4,4d1,4d0};

// This is used to convert the sample channel to the corresponding LED
// Most channels are invalid and will never be seen so we use 'x' as don't cares
const CHANNEL_TO_LED = {4bx,4bx,4bx,4bx,4bx,4bx,4d7,4d6,4d5,4d4,4d3,4d2,4bx,4bx,4d1,4d0};

.clk(clk), .rst(rst) {
pwm pwm[8](#WIDTH(10)); // 10bit PWM to show ADC value
dff ch[4]; // channel counter
}

always {
channel = LED_TO_CHANNEL[ch.q]; // set the channel to sample

pwm.value = 8x{{sample}}; // all PWM values are from sample
pwm.update = 8b0; // default to not updating

if (new_sample) { // when there is a new sample
pwm.update[CHANNEL_TO_LED[sample_channel]] = 1; // update the corresponding PWM channel
ch.d = ch.q + 1; // increment the channel we are sampling
if (ch.q == 7) // there are only 8 channels (0 to 7)
ch.d = 0; // restart at 0
}

leds = pwm.pulse; // send PWM signals to all LEDs
}
}

actually it not just the power. it seems ike it needs to be connected to my PC for it to work properly


RE: lucid analog input tutorial problem - caravandal - 05-19-2020

ok. so this problem seems to be because the mojo is expecting to be connected to a computer to empty its serial data before sampling more . 

what is the best way to disable this?