7i76e with 7i85 strange encoder output

12 Aug 2018 02:36 #115938 by Nitram
To provide some background, I have a 7i76e connected to a 7i85. The intention is to have spindle encoder on the 7i76e and utilize the remaining 4 encoder positions on the 7i85.
The 7i76e is flashed with the 7i76e_7i76x1_7i85x1D.bit firmware.
Am using Axis to test the setup.
Testing using Hal Config Watch, I get movement via the step gens etc, so the cards themselves are working as well as seeing enc counts responding on enc 4 (the encoder on the 7i763 board), see below.
Hal file:
loadrt hm2_eth board_ip="" config=" num_encoders=5 num_pwmgens=0 num_stepgens=5 sserial_port_0=00xxxx"

Have all 7i85 jumpers set to TTL (up).
Am using an MPG for testing. (A,B, +ve, -ve. No /A, /B).

When testing with the MPG on the 7i76e board (TB3, spindle encoder) the encoder counts for that encoder (enc 4), works correctly.

Moving to the 7i85 now where the slots for enc 0,1,2 and 3 are located. Testing with the MPG in enc slot 0 does not affect the enc 0 count. Testing with MPG in enc slot 1 causes counts for enc 0 AND 1 to respond. Testing the MPG in slot 2 does nothing. Testing the MPG in slot 3 causes enc 2 AND 3 counts to respond.

When HAL file is changed to num_encoders=6, the response is the same, i.e. enc 0 does nothing. enc 1 moves enc 0&1. enc 2 does nothing. enc 3 moves enc 2&3. enc 4 (on 7i76e) moves enc 4&5.

Have check the DB25 to IDC 26 cable and seems fine. Have reviewed the 7i76e pinout firmware for P1 via mesaflash and this seems to gel with the correct pinout for the DB25/IDC26 cable, although via the firmware, I only see two encoder channels on pins 8 through 13, channels 0 and 1. MuxedQCountSel is on pin 7. The firmware for the P0 (7i76e board) shows its encoder on channel 2. Not sure if this lack of firmware for channel 3 and 4 on the 7i85 is an issue, but please see the paragraph below regarding the following of the video. The fellow seemingly used the same firmware as I did, and got good results, but would be happy to revisit this if for some reason I installed the wrong firmware to access all four encoders on the 7i85...

Can anyone shed any light on this, specifically how to get the correct response from the 7i85 encoders 0,1,2 and 3?

Frustratingly, there is a video out there (in German, which I happen to speak as a second language) on the setup of a 7i76e with a 7i85 which was extremely helpful. I followed that precisely. In that video he goes on to test his setup with an MPG and the results are fine straight off the bat without any other parameter changes.

Many thanks.
12 Aug 2018 03:14 #115941 by PCW
You would get that response if the mux select pin was not connected from the 7I76E to the 7I85

(enc5 is a clone of enc4 because the 7I76Es encode is not muxed to this is expected)
The following user(s) said Thank You: Nitram
12 Aug 2018 16:08 #115967 by Nitram
Thanks for the reply Peter.

I've re-tested the cable with particular attention to the EncMuxSel (IO27), being pin 7 on the DB25 7i85 end and pin 13 on the IDC26 7i76e end. I get continuity and low resistance.
I also tested from the rear of both boards with the cable in place to rule out connections within the respective sockets and the result was the same, a good connection across Db25 pin 7 and IDC26 pin 13.
Just for the heck of it, I'll try with a different cable tomorrow. Unless there is a means of checking (via Hal watch/monitor??) I'm not sure where to head to test the output of the EncMuxSel pin back to the 7i76e. Clearly the encoder output is working and coming back to the controller, its just not being split up by the EncMuxSel signal.
Any thoughts greatly appreciated.
12 Aug 2018 16:52 #115969 by PCW
Does the 7I85 cable power jumper match the 7I76Es jumper?

5V cable power from 7I76E:

7I76E W7 UP 7I85 W3 UP

External power to 7I85:

7I76E W7 DOWN 7I85 W3 DOWN

(7I76E W7 is for P1 7I76E P2 uses W12)
12 Aug 2018 17:01 #115970 by Nitram
Yes. In this case the 7i85 is powered from the 7i76e.
7i76e W7 up
7i85 W3 up
7i85 cr1 is showing yellow.
Am getting 4.96v across all the power connectors in the 7i85 encoder slots (0 through 3).
12 Aug 2018 17:05 #115971 by PCW
So sounds like either failed 7I76E, 7I85 or bad cable

To try and narrow this down could you try this bitfile that puts the 7I85 on the second expansion connector:

12 Aug 2018 17:07 - 12 Aug 2018 17:08 #115972 by Nitram
Will do.
I'll flash it and test.
Will let you know the results shortly.
Last edit: 12 Aug 2018 17:08 by Nitram.
12 Aug 2018 17:16 #115973 by PCW
Remember after flashing that you must power cycle the 7I76E or run mesaflash with the --reload option to use the new firmware
12 Aug 2018 17:23 #115974 by Nitram
Ok Peter, here is what i did to confirm the test and the results.
1. Flashed the new firmware and did a --reload
2. Checked the new firmware with --readhmid
3. Confirmed that there was now assigned pinout to the P2 slot
4. This was the case and also P1 was now empty
5. Moved the IDC26 to EXP 2
6. Tested the 7i85 with the MPG

Results are the same as before with the previous firmware and 7i85 connected to EXP 1, specifically that enc slot 0 = nothing, enc slot 1 = counts on 0&1, enc slot 2 = nothing, enc slot 3 = counts on 2&3.

I.e. swapping 7i76e EXP ports did not alter the behavior.
12 Aug 2018 17:25 #115975 by PCW
OK so cable (short?) or failed 7i85
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