Linuxcnc 2.9.4 and Mesa 7i97T

7I97 analog outputs are generated from PWM
which requires some setup:


 ---PWM Generator signals/setup---
setp hm2_7i97.0.pwmgen.pwm_frequency 75000
setp  hm2_7i97.0.pwmgen.00.output-type 1 #PWM pin0
setp  hm2_7i97.0.pwmgen.00.offset-mode 1 # offset mode so 50% = 0
setp  hm2_7i97.0.pwmgen.00.scale  10
setp hm2_7i97.0.pwmgen.00.enable true

setp hm2_7i97.0.pwmgen.00.value 1.0


 

OK I figured it out almost
The analog pins are PWMs
But if i put this into my HAL:
setp hm2_[MESA](BOARD).0.pwmgen.00.dither true
setp hm2_[MESA](BOARD).0.pwmgen.00.output-type 1 #PWM pin0
setp hm2_[MESA](BOARD).0.pwmgen.00.offset-mode 1 # offset mode so 50% = 0
setp hm2_[MESA](BOARD).0.pwmgen.00.scale 10
setp hm2_[MESA](BOARD).0.pwmgen.00.value 1.0
I get 4.2 volt
Why? I have just double-checked 10/1 = 1

Do you get near 0V on the analog output
when the 7I97T is powered but LinuxCNC is not running?

Yes
The multimeter gave a jump to 0.5 volt in a glimpse . I don’t know for how long since the meter was set to store highest

I just tried to repeat the test.
This time the 0 was dead 0

Could it have any impact on the result that I also had the 24 v on the enable pin at the same time in the first test?

Not sure, sounds like the PWM is not setup properly

Can you run your test (where you expect 1V)

and in a terminal type

halcmd show all | grep pwm > pwm.txt

and post pwm.txt here



 

Here is pwm.txt - only analog=0 

OK those settings should result is a +1.0V output
(as they do here)

Possible reasons for a very different output voltage:

1. Measuring wrong pins ( analog output 0 would be measured from TB3 pin 4 to TB3 pin 3)

2. Marginal 5V supply to 7I97T

3. Problem with the voltmeter

4. Damaged 7I97T analog output driver

5. 7I97T analog output connected to shorted  load

  I think my voltage spikes seemed to disappear when I connected the board.So now im ready for the next step in my "simple retrofit machine"

• only one motor standing on the table waiting for action
  • enable directly to the Rexroth DKC11.3 drive

able to jog x motor in Axis.Unfortunately it didnt workWhen starting the configuration in Linuxcnc i get the message:
Note: Using POSIX realtime2573Stopping realtime threadsUnloading hal componentsNote: Using POSIX realtimeI have tried several things but now it seems that im stuck with this message.Any ideas?I attach report, hal and ini        

File Attachment:

File Name: homagretrofit.ini
File Size:3 KB

File Attachment:

File Name: main.hal
File Size:3 KB

File Attachment:

File Name: io.hal
File Size:0 KB

File Attachment:

File Name: linuxcncreport.txt
File Size:5 KB

You have basic7i97.hal in your .ini file but I think 
you wanted main. hal there instead.

That's why you get this error:

CANNOT FIND FILE FOR:basic7i97.hal

Thanks - of course -so simple i should have noticed it myself
Next error after changing name of hal in ini:

Debug file information:
Note: Using POSIX realtime
hm2_eth: rtapi_app_main: Resource temporarily unavailable (-11)
./main.hal:9: waitpid failed /usr/bin/rtapi_app hm2_eth
./main.hal:9: /usr/bin/rtapi_app exited without becoming ready
./main.hal:9: insmod for hm2_eth failed, returned -1
2077
Stopping realtime threads
Unloading hal components
Note: Using POSIX realtime

Why "temporarily" unavailable?