PSoC™ 5, 3 & 1 Forum Discussions

Hi,

I'm using a sequencing ADC offset in differential mode, with internal ±1.024V as reference, running at 1000KHz, 8 channels, and 12 bits resolution.

What is the best way to calibrate the gain and/or offset? I read in the datasheet that the gain is computed with adcGain = adcCounts * 10 / Volts, but this value I get varies largely from one input to the other. By doing an average, I get an offset on some channels up to 40mV. At low levels, though (~100mV), the offset is ~1mV. The large offsets are when the input is at 0.9V.

For the offset, the datasheet says to "short all inputs together". Should I also connect them to ground?

What's the best way to go about this problem?

Thank you,

Fred

Hi,

I'm using a CY8CKIT-059. I want to output 1.024V to pin 2.6. See below my top design. The opamp is in High Power mode.

At the start of main(), I call VREF_OPAMP_Start(). What is connected to pin 2.6 is a 10k resistor in series with a 10k NTC connected to ground. However, I only read 70mV at pin 2.6. What am I doing wrong?

Thank you,

Fred

Noobie to PSoC here,

I have the CY8CKIT-059 PSoC 5LP kit.

Background on what I am trying to accomplish: I am trying to read the velocity of a quadrature encoder which is 256 counts per revolution. I only need to measure the A or B wire because I do not care about direction.

The signal from the encoder is a 50-50 duty cycle square wave. My goal is to find the frequency of this square wave in hz.

I figure that I by measuring the frequency of the ticks of the rotary encoder, I can find the velocity. This sounds simple in my head but I'm having difficulty actually implementing this. Can someone point me in the right direction? (Remember, I'm a noobie)

Thanks,

Tanner Beard

Hi,

Does cypress has a PLC solution that supports SAE J2497 standard to communicate over power line with the different ECUs available in current truck/trailer market?

In a few designs I have noticed a glitch within the ADC cause it to return a weird and off scale values in certain low voltage ranges (0.08 to 0.09 volts in this case, there is another range a bit higher up). This glitch will affect all ADC readings with the SAR ADC if one input is in this range.

Edit: This happens on the CY8C5888CTI-LP097 / CY8CKIT-059.

Today I have taken the time to find and map those certain voltages only with the Delta Sigma ADC. The type of reference does change the glitch a bit but still within the same voltage range. I will try to get a 16-bit voltage source hooked up to try and get the other range where this happens (It is much smaller).

Testing Steps:

For a simple strategy of testing this phenomena, I interconnected an 8-bit DAC to a 16-bit Delta Sigma converter. Although this does happen with an external input.

The ADC data and control data for the DAC were sent over USB using the CDC driver.

The DAC is setup as 0-1.020 volts, low speed mode.

The ADC is setup as Vssa-2.048, Internal VREF 1.024, bypassed buffer. I have mapped the other buffers and one of a different reference.

Attached is raw CSV file (Voltage vs Time), source code, and an images of the graphed data.

Edit: Added data for a 2 channel SAR with a 14Bit Signal fed into the channels. It looks like there is a possible bit error. This also shows how it affects the whole device.

Thanks, can't wait to hear your feedback.

Nick

I need to add a SPIM to my project but my resorces are limited.

The device is a CY8C29666-24PVXI.

I only have DBC 22 and DBC 32 free to use.

I have GOE4,5,6 free.

I have GOO 0 to 7 free.

I have GIO 0 to 7 free.

Port 4 0 to 7 free.

I cant seem to figure out the routing for this device can any one help ?

Thanks

Gord

I am currently shipping a product. When it goes out the door it seems to be function as expected. After about 2-3 months there have been about 15-20 of them that have come back that don't seem to function at all. I do a checksum on them and the checksum doesn't match the original program. The checksums from non-working device to non-working device all seem to be different.

I'll post the project and the checksum information on here on Monday as I know that will be more helpful. I just wanted to get the ball rolling on this question right now.

My first thoughts is that the emulated EEPROM I'm using in this project is overwriting and corrupting program memory. Is there a way to explicitly protect the program memory from being overwritten by the emulated EEPROM?

Any preliminary help would be appreciated. Thanks!

PSOC3突然无法编程。