Reading 2 ADC Channels ulp
Posted: Thu Feb 21, 2019 1:41 am
Hi everyone!
I'm having an Issue with ULP assembler.
I need to read 2 digial inputs with the ulp core.
The way I'm trying to do it is by measuring channel 6 of ADC1 (I'm aware you can't use the second one while using wifi) and comparing the value with a treshold. This works fine with 1 channel. Now I need to measure a second one. so i change the ADC channel and compare it again, but it only works with the first one.
What am I doing wrong?
Do you know a more efficient way of doing it? Kinda like a digital read?
Help would be greatly appreciated, I'm a total assembler noob.
Board: ESP-Wroom-32 dev module
code:
Thanks
The Iron Mechanic
I'm having an Issue with ULP assembler.
I need to read 2 digial inputs with the ulp core.
The way I'm trying to do it is by measuring channel 6 of ADC1 (I'm aware you can't use the second one while using wifi) and comparing the value with a treshold. This works fine with 1 channel. Now I need to measure a second one. so i change the ADC channel and compare it again, but it only works with the first one.
What am I doing wrong?
Do you know a more efficient way of doing it? Kinda like a digital read?
Help would be greatly appreciated, I'm a total assembler noob.
Board: ESP-Wroom-32 dev module
code:
Code: Select all
#include "soc/rtc_cntl_reg.h"
#include "soc/rtc_io_reg.h"
#include "soc/soc_ulp.h"
/* ADC1 channel 6, GPIO34 */
.set adc_channel, 6
/* Configure the number of ADC samples to average on each measurement.
For convenience, make it a power of 2. */
.set adc_oversampling_factor_log, 1
.set adc_oversampling_factor, (1 << adc_oversampling_factor_log)
/* Define variables, which go into .bss section (zero-initialized data) */
.bss
/* Low threshold of ADC reading.
Set by the main program. */
.global low_threshold
low_threshold: .long 0
/* High threshold of ADC reading.
Set by the main program. */
.global high_threshold
high_threshold: .long 0
/* Counter of measurements done */
.global sample_counter
sample_counter:
.long 0
.global ADC_reading
ADC_reading:
.long 0
.global ADC_reading2
ADC_reading2:
.long 0
/* Code goes into .text section */
.text
.global entry
entry:
/*DEBUG*/
/* Disable hold of GPIO13 output */
WRITE_RTC_REG(RTC_IO_TOUCH_PAD4_REG, RTC_IO_TOUCH_PAD4_HOLD_S, 1, 0)
/* Set the GPIO13 output HIGH */
WRITE_RTC_REG(RTC_GPIO_OUT_W1TS_REG, RTC_GPIO_OUT_DATA_W1TS_S + 14, 1, 1)
/* increment sample counter */
move r3, sample_counter
ld R2, r3, 0
add R2, R2, 1
st R2, r3, 0
/* do measurements using ADC */
/* r0 will be used as accumulator */
move r0, 0
/* initialize the loop counter */
stage_rst
measure:
/* measure and add value to accumulator */
adc r1, 0, adc_channel + 1
add r0, r0, r1
/* increment loop counter and check exit condition */
stage_inc 1
jumps measure, adc_oversampling_factor, lt
/* divide accumulator by adc_oversampling_factor.
Since it is chosen as a power of two, use right shift */
rsh r0, r0, adc_oversampling_factor_log
/* averaged value is now in r0; store it into ADC_reading */
move r3, ADC_reading
st r0, r3, 0
/* compare with low_threshold; wake up if value < low_threshold */
/*move r3, low_threshold
ld r3, r3, 0
sub r3, r0, r3
jump led_off, ov
/* compare with high_threshold; wake up if value > high_threshold */
move r3, high_threshold
ld r3, r3, 0
sub r3, r3, r0
jump wake_up, ov
/*ADC1 channel 5, GPIO33*/
.set adc_channel, 5
/* Configure the number of ADC samples to average on each measurement.
For convenience, make it a power of 2. */
.set adc_oversampling_factor_log, 1
.set adc_oversampling_factor, (1 << adc_oversampling_factor_log)
/* Define variables, which go into .bss section (zero-initialized data) */
/*.bss*/
/*move r0, 0*/
/* initialize the loop counter */
/*stage_rst*/
measure2:
/* measure and add value to accumulator */
adc r1, 0, adc_channel + 1
add r0, r0, r1
/* increment loop counter and check exit condition */
stage_inc 1
jumps measure2, adc_oversampling_factor, lt
/* divide accumulator by adc_oversampling_factor.
Since it is chosen as a power of two, use right shift */
rsh r0, r0, adc_oversampling_factor_log
/* averaged value is now in r0; store it into ADC_reading2 */
move r3, ADC_reading2
st r0, r3, 0
/* compare with low_threshold; wake up if value < low_threshold */
/*move r3, low_threshold
ld r3, r3, 0
sub r3, r0, r3
jump led_off, ov*/
/* compare with high_threshold; wake up if value > high_threshold */
move r3, high_threshold
ld r3, r3, 0
sub r3, r3, r0
jump wake_up, ov
/* value within range, end the program */
.global exit
exit:
/*DEBUG*/
/* Set the GPIO13 output LOW (clear output) to signal that ULP is now going down */
WRITE_RTC_REG(RTC_GPIO_OUT_W1TC_REG, RTC_GPIO_OUT_DATA_W1TC_S + 14, 1, 1)
/* Enable hold on GPIO13 output */
WRITE_RTC_REG(RTC_IO_TOUCH_PAD4_REG, RTC_IO_TOUCH_PAD4_HOLD_S, 1, 1)
halt
.global wake_up
wake_up:
/* Check if the system can be woken up */
READ_RTC_FIELD(RTC_CNTL_LOW_POWER_ST_REG, RTC_CNTL_RDY_FOR_WAKEUP)
and r0, r0, 1
jump exit, eq
/* Wake up the SoC, end program */
wake
WRITE_RTC_FIELD(RTC_CNTL_STATE0_REG, RTC_CNTL_ULP_CP_SLP_TIMER_EN, 0)
jump exitThe Iron Mechanic