Anyone seen this?

blazini36 wrote:

Lol let's bring this back to EtherCAT, none of that has anything to do with this thread. It's not even worth talking about comparing dev boards that use MCUs that don't have any proper peripherals for machine control vs one that has all the peripherals. There's a reason actual company's use STM32s and IMX1052/1062 for CNC controllers...they don't use RP2040s and ESP32s. They have their own uses, machine control is not one of them. Niether of them have proper hardware encoder peripherals and no, the PIO doesn't compare in any way to an IMX1062's hardware encoders. So build something with an Rpi Pico, and be happy you saved $20 over using a Teensy 4.1 then be dissapointed that it's about 1/4 the clock speed and can count an encoder about 1/50th the frequency. Not really worth the effort to me.

So different use cases.

Teensy is excellent for more complicated / demanding application: high speed encoder input etc.

But overkill and expensive for simple GPIO device.

If we want low cost EtherCat GPIO, then $20 does matter.
Beckoff / real brand name GPIO is $$$, like $200-500.
Chinese GPIO is $70-150, but documentation, support etc. poor.

If we can make a simple GPIO that competes or does better than the Chinese price I think it would be worthwhile.

LAN9252 can do 16 GPIO without an MCU.

Most EtherCat setups will have EtherCat Servo drives or stepper drives -> so no step generation required.
Encoder input useful sometimes for adding linear encoders to a machine, though expect the market would be small.

Everyone needs GPIO.

The LAN9254 can do 32 GPIO by itself (basically the same price as LAN9252/LAN9253)

Good point PCW, forgot about the increase IO with LAN9254

The hardware ex China for I/O is cheap enough. The Deiwu  has 16 in nd 16 out is about AUD $100 landed.
www.alibaba.com/product-detail/Industria...image.56f917c6Qu9Q17

For a bit more you can buy Rtelligent 16 in 16 out with PWM and documentation! This will let you control a conventional VFD

I have used both of these.

The modules that are not readilly available are MPG counters and encoders. This is where Beckhoff really gouge you. That is the two functions I would start with. There is one Chinese module that includes I/O, modbus, encoders and counterrs which is a reasonable price. About AUD $200 from memory. Way under Beckhoff.
 

Thanks Rod

The Rtelligent RTEC1616 does have an acceptable manual with wiring diagrams etc.

Found the GPIO module with Modbus: CATIO-A
www.aliexpress.com/item/1005005340849270.html
From "Lucking Store" www.aliexpress.com/store/1100369030

rodw wrote:

The hardware ex China for I/O is cheap enough. The Deiwu  has 16 in nd 16 out is about AUD $100 landed.
www.alibaba.com/product-detail/Industria...image.56f917c6Qu9Q17

For a bit more you can buy Rtelligent 16 in 16 out with PWM and documentation! This will let you control a conventional VFD

I have used both of these.

The modules that are not readilly available are MPG counters and encoders. This is where Beckhoff really gouge you. That is the two functions I would start with. There is one Chinese module that includes I/O, modbus, encoders and counterrs which is a reasonable price. About AUD $200 from memory. Way under Beckhoff.

 

Thanks for the info Rod, you probably have a better idea than anyone else about the EtherCAT market.

None of that stuff is really an issue, some of it's in my control panel PCB. Once I get that EtherCAT'd I'll start looking at other things.

Believe it of not the hardest thing about it is figuring out good form factors, where to put connectors etc. I generally just make stuff that fits well in the box I'm stuffing it in.

PCW wrote:

The LAN9254 can do 32 GPIO by itself (basically the same price as LAN9252/LAN9253)
 

Good call, it's literally about $1 more than the 52. I didn't really do the shopping As I don't need the baked in GPIO for the current thing.

 

I might add that building a custom Cia402 homing module would allow you to home some drives to a hard stop so no I/O would be required for limits. But most drives have some inputs for homing/limits and an output for an alarm. So its really just the encoder needed until you add a tool changer or something.... Plan out what an average machine needs. You might be surprised how little I/O is required.

rodw wrote:

I might add that building a custom Cia402 homing module would allow you to home some drives to a hard stop so no I/O would be required for limits. But most drives have some inputs for homing/limits and an output for an alarm. So its really just the encoder needed until you add a tool changer or something.... Plan out what an average machine needs. You might be surprised how little I/O is required.
 

Eh....sensorless homing has always bothered me...

I've noticed the same about EtherCAT drives having IO ports. You are right about a full etherCAT machine not really needing much separate IO except for the fact that EtherCAT drives are still really expensive. I think that's where your encoder/pulse/io modules come in, so you can still do everything over EtherCAT from the host. Your basically doing the Mesa card's job with some EtherCAT stuff at that point so I'm not 100% certain that there's a big reason to do it over just using a Mesa card. I'll have to figure out what kind of counting/pulse frequencies you can expect from a high end microcontroller vs what the FPGA cards can do to see if it's even worth talking about.

I think you use ethercat or you don't. Even the Rtelligent ECT60 drive can be configured with min limit, max limit and home using internal Inputs if you don't want to use sensorless. It also has two outputs, usually for alarm (we should use) and brake (rarely used) but can be used as a generic output. I suspect sensorless is more repeatable.

Whether you use Mesa or Ethercat is a matter for personal preference but if you are building a machine for resale customers will expect to see ethercat. The added cost may well be offset by reduced labour in the wiring.