Retrofitting a 1986 Maho MH400E

You can work out the port and channel of any smart-serial device by looking at the HAL pins.

hm2_5i25.0.7i84.1.2..... means that the 7i84 is on port 1 channel 2.

x turns off a channel, making the pins available for GPIO, but as they would be GPIO on an RJ45 connector it would be unusual to use them as such.

In your setup sserial port 0 (7i77) only has 3 channels. So in fact sserial_port_0=3xx would be sufficient. Though that will turn off the serial expansion port on the 7i77 (which could be usefully used as GPIO) I think it will also turn off the analog outputs. (Digital IO is on sserial channel 0, so I think that analog-out is on sserial channel 1. The HAL pins will make that clear, as described above)
Looking at sample configs, digital IO and analog in pins have names like hm2_5i25.0.7i77.0.0.input-08 and analog outs have names like hm2_5i25.0.7i77.0.1.analogena showing that they are on different channels of the same port.

So, sserial_port_0=3xx is all that is needed, if you really do want to disable the expansion port and analog output. (I bet you don't)

Hi andypugh,

thanx for the details.
The dotted notation like ...0.1... was clear to me but the manual for the 7i77 does not reveal that the analogue section and expansion port is on channel one and two, at least not explicitly.
Nevertheless I finally got my machine working for the first time today with:
sserial_port_0=300xxx
sserial_port_1=xxx0x2xx

All three axis move and the spindle-gear switches.
A big success for today !

Hanno

The 7I77 manual is pretty generic, there's no actual fixed channel numbering.
Most configs do have the first 7I77 digital section on channel 0 and analog section on channel 1 but that's entirely determined by the FPGA firmware.
You can determine the actual mapping by looking at the Firmware pinout in conjunction with the 7I77 pinout

Yes, that was my mistake not having in mind that the FPGA can run different firmwares having different (channel) setups then.

Update:
I went to the shop again yesterday as I could not wait to play a little bit.
I even dared homing the axes
The low room temperature of 2°C might have been the cause but I noticed the servos to be much noisier than they were on the Philips controller.
I think the tuning still needs some improvement.

First I'm going to test if there is any drift on an axis like Mark has.
Mark: Could you please send me the G-Code of that circle plot ?

Hanmon congratulation on the Maho conversion ! Braving a 2.degree C shop sounds like you are excited . Maybe consider making a plastic film tent with heater .
Interesting about the servo sound of Phillips vers Linux CNC . Would be very interesting to have a compare and contrast of the two controllers when your conversion is further completed .Such as what are your thoughts about functional difference between the two controllers.
Have you looked at

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gnipsel.com/linuxcnc/tuning/index.html JThorton servo tune ?
What velocity in machine units per second , are you using? Also wonder what Velocity and PID values Mark is using .?

PCW seems to have very good suggestions/answers about servo tuning .
Hope you check if the Lub pump and oilers are working.

Thanks for the updates
Bob

Hi Bob,
I'm really excited about the progress.
Thank you for the link !
I haven't yet engaged myself with pid-tuning.
Mark has already done that and I took his values initially.

The lubrication pump is a good point, as in my version of the Maho it is called "motion dependent lubrication" (bewegungsabhängige Schmierung) and was controlled by the Philips 432. The lubrication pump has an input for turning on and an output return signal which I have both already connected the 7i84.
I now have to find out the original/sufficient on-interval of that pump.