Advanced Search

Hello again Scotta!

We've continued testing on the octopus board, we have gotten movement but it seems that the SPI communication with the board seems to keep dying. We got the serial output:

Creating a std module

Remora PRU - Programmable Realtime Unit 

 Mbed-OS6 

 Remora-spi Driver 

## Entering SETUP state
1. Reading json configuration file
Mounting the filesystem... OK
Opening "/fs/config.txt"... OK
Json config file lenght = 1996
Closing "/fs/config.txt"... 
2. Setting up DMA and threads
Initialising SPI1 slave
Initialising DMA for SPI

3. Parsing json configuration file
Config deserialisation - Deserialization succeeded

4. Config threads
Creating thread 40000
Creating thread 1000
Creating thread 57600

5. Loading modules

Servo thread object
Reset pin
Make Reset Pin at pin PC_15

Creating a std module
Creating Pin @
  port = GPIOC
  pin = 15

Servo thread object
eStop
Make eStop at pin PG_12

Creating a std module
Creating Pin @
  port = GPIOG
  pin = 12

Servo thread object
Spindle
Make PWM at pin PB_0

Creating a std module
Creating variable frequency Hardware PWM at pin PB_0
Creating Pin @
  port = GPIOB
  pin = 0

Base thread object
X - Joint 0 step generator

Creating a std module
Creating Pin @
  port = GPIOG
  pin = 2
Creating Pin @
  port = GPIOF
  pin = 9
Creating Pin @
  port = GPIOF
  pin = 10

Base thread object
Y1 - Joint 1 step generator

Creating a std module
Creating Pin @
  port = GPIOF
  pin = 1
Creating Pin @
  port = GPIOC
  pin = 13
Creating Pin @
  port = GPIOF
  pin = 0

Base thread object
Y2 - Joint 1 step generator

Creating a std module
Creating Pin @
  port = GPIOD
  pin = 4
Creating Pin @
  port = GPIOE
  pin = 2
Creating Pin @
  port = GPIOE
  pin = 3

Base thread object
Z - Joint 2 step generator

Creating a std module
Creating Pin @
  port = GPIOE
  pin = 0
Creating Pin @
  port = GPIOE
  pin = 6
Creating Pin @
  port = GPIOA
  pin = 14

Servo thread object
X min
Make Digital Input at pin PG_6

Creating a std module
  Setting pin as No Pull
Creating Pin @
  port = GPIOG
  pin = 6

Servo thread object
Y min
Make Digital Input at pin PG_9

Creating a std module
  Setting pin as No Pull
Creating Pin @
  port = GPIOG
  pin = 9

Servo thread object
Z min
Make Digital Input at pin PG_10

Creating a std module
  Setting pin as No Pull
Creating Pin @
  port = GPIOG
  pin = 10

Servo thread object
Probe
Make Digital Input at pin PG_11

Creating a std module
  Setting pin as No Pull
Creating Pin @
  port = GPIOG
  pin = 11

## Entering START state

Starting the BASE thread
Registering interrupt for interrupt number = 24
    power on Timer 9

Starting the SERVO thread
Registering interrupt for interrupt number = 25
    power on Timer 10

## Entering IDLE state

## Entering RUNNING state

## Entering RESET state
   Resetting rxBuffer

## Entering IDLE state


This last bit is where we are running into a wall, we are not sure what is causing this.
 

Consistent position errors after a long program could indicate a step timing
or polarity issue. Too low direction setup or hold times could cause a lost step
at reversals. Wrong step polarity can also cause this issue as stepping on the
trailing edge of the step pulse (rather then the expected leading edge) will
decrease the expected hold time.

It might be worth either inverting the step polarity or increasing the setup/hold times,
at least to see if it changes anything.

Some of the cheaper fixed bearing blocks are sold with non angular contact bearings, this is something to check.
Until you perform a backlash test, and yes this can manifest as repeatable, you can not rule out a mechanical issue.

Thanks Rod. I'll look into upgrading to 2.10.