I am tyring to debug an issue with the MPU9250 driver on custome hardware. The issue is that on power up the MPU9250 is sending correct data, but the STM32F7 only receives a few reads and then all SPI reads all drop to 0x00. Here is an output from the debug serial. Does anyone have any ideas on this?
WARN [mpu9250] SPI_INTERNAL
WARN [mpu9250] main::start busid: 3, Rotation: 0, external: 0
INFO [mpu9250] main::start_bus)
INFO [mpu9250] MPU9250_SPI::init()
INFO [mpu9250] MPU9250_SPI::read - reg: 117, count: 1
INFO [mpu9250] pbuff - 536901628:
spi_setmode: mode=3
spi_setbits: nbits=8
spi_exchange: txbuffer=200077fc rxbuffer=200077fc nwords=2
spi_send: Sent: f5 Return: 00 Status: 02
spi_send: Sent: 00 Return: 71 Status: 02
INFO [mpu9250] OK - SPI data received, data: 0 71 536901628 536901629
INFO [mpu9250] MPU9250_SPI:probe() found MPU! 113
MPU9250 on SPI bus 4 at 1 (1000 KHz)
INFO [mpu9250] MPU9250::init()
INFO [mpu9250] MPU9250::probe()
INFO [mpu9250] MPU9250_SPI::read - reg: 117, count: 1
INFO [mpu9250] pbuff - 536901468:
spi_setmode: mode=3
spi_setbits: nbits=8
spi_exchange: txbuffer=2000775c rxbuffer=2000775c nwords=2
spi_send: Sent: f5 Return: ff Status: 02
spi_send: Sent: 00 Return: 71 Status: 02
INFO [mpu9250] OK - SPI data received, data: ff 71 536901468 536901469
INFO [mpu9250] MPU9250::reset_mpu()
spi_setmode: mode=3
spi_setbits: nbits=8
spi_exchange: txbuffer=20007724 rxbuffer=20007724 nwords=2
spi_send: Sent: 6b Return: ff Status: 02
spi_send: Sent: 80 Return: ff Status: 02
spi_setmode: mode=3
spi_setbits: nbits=8
spi_exchange: txbuffer=20007714 rxbuffer=20007714 nwords=2
spi_send: Sent: 6b Return: 00 Status: 02
spi_send: Sent: 01 Return: 00 Status: 02
spi_setmode: mode=3
spi_setbits: nbits=8
spi_exchange: txbuffer=20007714 rxbuffer=20007714 nwords=2
spi_send: Sent: 6c Return: 00 Status: 02
spi_send: Sent: 00 Return: 00 Status: 02
spi_setmode: mode=3
spi_setbits: nbits=8
spi_exchange: txbuffer=20007714 rxbuffer=20007714 nwords=2
spi_send: Sent: 6a Return: 00 Status: 02
spi_send: Sent: 10 Return: 00 Status: 02