AIS2120x sensor read data issue

[anandhram1988]

Hi , i am trying to read the sensor data of AIS2120x only for sensor ID type , i can see from the bus the data is transferred correctly, but i don't receive any data back from sensor rather its only 0.

i have attached the code snippet for this test, any leads will be helpful. JHo.1

@JHo.1 and @Eleon BORLINI @CJeff.1 

test 1:

CS_low();

Sensor_Write(0xD1,0x80,ubAisSensor );  // command to read address 0x0C/REG_ID_SENSOR_TYPE from AIS2120x

                                            // according to 32 byte cmmand format                                 Sensor_Write(0x00,ubCrcVal,ubAisSensor );  

CS_high();

Test 2:

CS_low();

Sensor_Write(0x8C,0x00,ubAisSensor ); // command to read address 0x0C/REG_ID_SENSOR_TYPE      from AIS2120x

set_high();

//Sensor interface 

void Sensor_Write(uint8 addr, uint8 Data,(uint8 Sensor) {

 // application specific

spi_Write(addr);

delay();

spi_Write(Data);

}

//receive ISR

uint8 ubSpiStatus;

uint8 RxData;

_INTERRUPT_VOID SPI_vRxISR (void)

{

if(SPIS==0xA0)

{

RxData = SPID;

ubSpiStatus = 1;

}

}

spi_Write(uint8 addr, uint8 Data,uint8 ubAisSensor)

{

while (!(SPIS)); // Wait until transmit buffer is empty

SPID = data;

while(!ubSpiStatus);

ubSpiStatus = 0;

while (!(SPIS)); // Wait until transmit buffer is empty

SPID = data;

while(!ubSpiStatus);

ubSpiStatus = 0;

appl(RxData); //evaluate data

}

i use nxp 8 bit mcu : MC9S08SH32

MCU is 5v output, level shifter used between MCU and sensor to downgrade voltage to 3V3 ,

[Andrew Neil]

You seem to have forgotten how to post source code ?

---

@anandhram1988 wrote:

 i don't receive any data back from sensor rather its only 0.

---

Your code uses only spi_Write() - there are no reads!

[anandhram1988]

I have edited, the receive ISR, please inform if anything else required 

[Andrew Neil]

Please read  how to post source code - apply the proper formatting.

You need to show your implementation of spi_Write().

You haven't said what microcontroller you're using, what board it's on. or how it's connected to the sensor.

Please show schematics.

See: How to write your question to maximize your chances to find a solution.

[anandhram1988]

Thanks for reply,updated the main message also

spi_Write(uint8 data)
{
while (!(SPIS)); // Wait until transmit buffer is empty
SPID = data)

while(!ubSpiStatus);
ubSpiStatus = 0;
appl(RxData); //evaluate data
}

i use nxp 8 bit mcu : MC9S08SH32

MCU is 5v output, level shifter used between MCU and sensor to downgrade voltage to 3V3 ,

SPI bus log attached

[Andrew Neil]

You still haven't read how to post source code - have you?

https://community.st.com/t5/community-guidelines/how-to-insert-source-code/ta-p/693413

---

@anandhram1988 wrote:

MCU is 5v output, level shifter used between MCU and sensor to downgrade voltage to 3V3

---

Again, Please show the schematic!

---

@anandhram1988 wrote:

SPI bus log attached

---

Is that before or after the level shifter?

Show what's actually happening at the sensor's pins.

Have you also looked at the signals on an oscilloscope? Are they clean?

PS:

---

@anandhram1988 wrote:

i use nxp 8 bit mcu : MC9S08SH32. MCU is 5v output,

---

That device can run at 3.3V.

As a test, have you tried without the level shifter - running the MCU at 3.3V ?

[anandhram1988]

test 1:
CS_low();
spi_Write(0xD1,0x80,ubAisSensor );  // command to read address 0x0C/REG_ID_SENSOR_TYPE from AIS2120x
                                            // according to 32 byte cmmand format                                 spi_Write(0x00,ubCrcVal,ubAisSensor );  
CS_high();
 
Test 2:
CS_low();
spi_Write(0x8C,0x00,ubAisSensor ); // command to read address 0x0C/REG_ID_SENSOR_TYPE      from AIS2120x
set_high();
 
//receive ISR
uint8 ubSpiStatus;
uint8 RxData;
_INTERRUPT_VOID SPI_vRxISR (void)
{
if(SPIS==0xA0)
{
RxData = SPID;
ubSpiStatus = 1;
}
 
}
spi_Write(uint8 data)
{
while (!(SPIS)); // Wait until transmit buffer is empty
SPID = data;

while(!ubSpiStatus);
ubSpiStatus = 0;
appl(RxData); //evaluate data
}

[anandhram1988]

SPI trace attached already from the sensor pins, i have not tried with 3,3MCU voltage since 5 V is operating for this mcu

Above trace is recorded from sensor pins

[Andrew Neil]

---

@anandhram1988 wrote:

test 1:
CS_low();
spi_Write(0xD1,0x80,ubAisSensor );  // command to read address 0x0C/REG_ID_SENSOR_TYPE from AIS2120x
                                    // according to 32 byte cmmand format                                 spi_Write(0x00,ubCrcVal,ubAisSensor );  
CS_high();
 
Test 2:
CS_low();
spi_Write(0x8C,0x00,ubAisSensor ); // command to read address 0x0C/REG_ID_SENSOR_TYPE from AIS2120x
set_high();

---

In the above code, you supply three parameters to each spi_Write() call

But your definition of spi_Write() takes only one parameter

---

@anandhram1988 wrote:

spi_Write(uint8 data)
{

---

Also:

@anandhram1988 wrote:

i use nxp 8 bit mcu : MC9S08SH32. MCU is 5v output,

That device can run at 3.3V.

As a test, have you tried without the level shifter - running the MCU at 3.3V ?

[anandhram1988]

test 1:
CS_low();
Sensor_Write(0xD1,0x80,ubAisSensor );  // command to read address 0x0C/REG_ID_SENSOR_TYPE from AIS2120x
                                            // according to 32 byte cmmand format                                 Sensor_Write(0x00,ubCrcVal,ubAisSensor );  
CS_high();
 
Test 2:
CS_low();
Sensor_Write(0x8C,0x00,ubAisSensor ); // command to read address 0x0C/REG_ID_SENSOR_TYPE      from AIS2120x
set_high();

//Sensor interface 

void Sensor_Write(uint8 addr, uint8 Data,(uint8 Sensor) {
 // application specific
	spi_Write(addr);
	delay();
	spi_Write(Data);
}
 
//receive ISR
uint8 ubSpiStatus;
uint8 RxData;
_INTERRUPT_VOID SPI_vRxISR (void)
{
if(SPIS==0xA0)
{
RxData = SPID;
ubSpiStatus = 1;
}
 
}
spi_Write(uint8 addr, uint8 Data,uint8 ubAisSensor)
{
while (!(SPIS)); // Wait until transmit buffer is empty
SPID = data;

while(!ubSpiStatus);
ubSpiStatus = 0;

while (!(SPIS)); // Wait until transmit buffer is empty
SPID = data;

while(!ubSpiStatus);
ubSpiStatus = 0;
appl(RxData); //evaluate data
}