[samco]

You need 3 pins for rigid tapping... A,B and index.

[brianbonedoc]

Actually if I recall correctly the second port on the MESA card is open and that would be a better option. I think the basic mesa flash may even have quadrature encoder already flashed into it. I know the lathe one does.

Connecting the pins isn't that hard in the hal file. You can see some examples online and work from there. I know for my old lathe, I did it and it worked out great.

[kstrauss]

Does Mesa (or anyone else) make a BOB to connect to the spare port? If so, what is the part number?

[jcposada]

You can use a C10 breakout.

[kstrauss]

I assume that you mean https://cnc4pc.com/motion-control/br...face-card.html
What cable do I need between the Mesa and the C10?

[brianbonedoc]

So the tormach lathe pin file has quadrature encoder in the mesa firmware on both ports:

IO Connections for P3

Pin# I/O Pri. func Sec. func Chan Pin func Pin Dir



1 0 IOPort StepGen 2 Step (Out)

14 1 IOPort None

2 2 IOPort StepGen 0 Dir (Out)

15 3 IOPort None

3 4 IOPort StepGen 0 Step (Out)

16 5 IOPort QCount 1 Quad-A (In)

4 6 IOPort StepGen 1 Dir (Out)

17 7 IOPort PWMGen 0 PWM (Out)

5 8 IOPort StepGen 1 Step (Out)

6 9 IOPort None

7 10 IOPort None

8 11 IOPort None

9 12 IOPort None

10 13 IOPort QCount 0 Quad-IDX (In)

11 14 IOPort QCount 0 Quad-A (In)

12 15 IOPort QCount 0 Quad-B (In)

13 16 IOPort None



IO Connections for P2

Pin# I/O Pri. func Sec. func Chan Pin func Pin Dir



1 17 IOPort StepGen 5 Step (Out)

14 18 IOPort None

2 19 IOPort StepGen 3 Dir (Out)

15 20 IOPort None

3 21 IOPort StepGen 3 Step (Out)

16 22 IOPort QCount 3 Quad-A (In)

4 23 IOPort StepGen 4 Dir (Out)

17 24 IOPort PWMGen 1 PWM (Out)

5 25 IOPort StepGen 4 Step (Out)

6 26 IOPort None

7 27 IOPort None

8 28 IOPort None

9 29 IOPort None

10 30 IOPort QCount 2 Quad-IDX (In)

11 31 IOPort QCount 2 Quad-A (In)

12 32 IOPort QCount 2 Quad-B (In)

13 33 IOPort None


But not sure about the Mill firmware (I only see index pulse) as the pin file doesn't list whats on the P2 connector of the mesa.
################################################## ######################
# 5i25
# Configuration pin-out:
#
# IO Connections for P3
# Mill Function Pin# I/O Pri. func Sec. func Chan Pin func Pin Dir
#
# Spindle Speed 1 0 IOPort StepGen 4 Step/Table1 (Out)
# Coolant 14 1 IOPort None (Out)
# X Direction 2 2 IOPort StepGen 0 Dir/Table2 (Out)
# Estop Reset 15 3 IOPort None (In)
# X Step 3 4 IOPort StepGen 0 Step/Table1 (Out)
# Spindle Dir 16 5 IOPort None (Out)
# Y Direction 4 6 IOPort StepGen 1 Dir/Table2 (Out)
# Charge Pump 17 7 IOPort PWM 0 PWM (Out)
# Y Step 5 8 IOPort StepGen 1 Step/Table1 (Out)
# Z Direction 6 9 IOPort StepGen 2 Dir/Table2 (Out)
# Z Step 7 10 IOPort StepGen 2 Step/Table1 (Out)
# A Direction 8 11 IOPort StepGen 3 Dir/Table2 (Out)
# A Step 9 12 IOPort StepGen 3 Step/Table1 (Out)
# X Limit 10 13 IOPort None (In)
# Y Limit 11 14 IOPort None (In)
# Z Limit 12 15 IOPort None (In)
# Probe In 13 16 IOPort None (In)
# 1 PPR encoder 13 16 IOPort QCount 0 Quad-IDX (in)
#

[PCW_MESA]

You can read the pinout from any loaded configuration with:

sudo mesaflash --device 5i25 --readhmid

(from a terminal window)

[jcposada]

You can use a C10 breakout.

Sorry I should have been more clear. You can use a C10 board (yes that is the one) to break out the built-in parallel port which Pathpilot can also use.

[kstrauss]

Sorry to belabor the point but I'm confused. I assumed that one would use the second port on the 5i25 in order to use the quadrature capability on the Mesa card. Mesa has a 7i76 which provides isolation but I'm unclear what cable is required to connect it to the internal port on the Mesa card.

[SoCalPlaneDoc]

You need 3 pins for rigid tapping... A,B and index.

Well durn it, that means the encoder wheel I designed wont work.
No biggie, I've got a couple of BEI industrial encoders that should do the trick.. couple of MX pulleys and I should be back on track.
Might still make the wheel though, could using something to play with color anodize....

[jcposada]

Sorry to belabor the point but I'm confused. I assumed that one would use the second port on the 5i25 in order to use the quadrature capability on the Mesa card. Mesa has a 7i76 which provides isolation but I'm unclear what cable is required to connect it to the internal port on the Mesa card.

See post #23. That cable will give you access to the second parallel port on the Mesa card. Then connect that to a C10 bob with a standard parallel cable.

[PCW_MESA]

Sorry to belabor the point but I'm confused. I assumed that one would use the second port on the 5i25 in order to use the quadrature capability on the Mesa card. Mesa has a 7i76 which provides isolation but I'm unclear what cable is required to connect it to the internal port on the Mesa card.

You typically use 2 cables for this, the first is a short flat cable from the internal 5I25 connector
to a PC bracket mounted DB25F (to get the signals out of the PC) and then a standard DB25
male-male IEEE-1284 printer cable to go to the 7I76

DB25F-IDC26 CABLE
http://store.mesanet.com/index.php?r...=239&search=db

for example (these are generally available from Monoprice etc)

[SoCalPlaneDoc]

Sorry to belabor the point but I'm confused. I assumed that one would use the second port on the 5i25 in order to use the quadrature capability on the Mesa card. Mesa has a 7i76 which provides isolation but I'm unclear what cable is required to connect it to the internal port on the Mesa card.

Looks to me cable like this one should do the trick:
※※※NEW ※※※ DB25 LPT1 Parallel 25-Pin Printer Port Full Height Bracket 12" Cable | eBay

You'd still need another 7i76 and cable though. Does anyone see and operational advantage to this over an old-fashioned printer port and BOB?

[PCW_MESA]

You can use a standard parallel port BOB with the second 5I25 port (a 7I76 is extreme overkill for just adding an encoder)

Advantages of using second 5i25 port:

1. Real encoder counter, so no base thread needed (widens host PC choices since you do not need very good real time latency for just a 1 KHz servo thread )
also supports high resolution encoders

2. Only one card needed if theres no MB parallel port (say on mini-ITX MBs which have only one available PCI/PCIE slot)

Advantages of using parallel port:

1. Somewhat simpler setup ( no firmware changes)

2. if a plug-in PP is used a damaged port is a $10 replacement as opposed to a $90 replacement for a 5I25

[kstrauss]

I assume that it depends on the shaft encoder. With a 1000 line encoder I think that means 2000 transitions/rev/channel. At 2000 rpm this is 67000 transitions/sec times two (A,B channels) or 133K/sec or a transition every 7.5 microseconds. That seems excessive for the PC to have to process each of them via the parallel port. (Please check my arithmetic!) On the other hand perhaps a 1000 line encoder is huge overkill just for tapping. What sort of encoder do commercial machines such as a Haas use?

[PCW_MESA]

People have done have done tapping successfully with LinuxCNC using fairly crude encoders (say ~ 50 lines or 200 counts)
Finer threads will be less picky about the spindle feedback because the Z axis errors during reversal are correspondingly smaller

[SoCalPlaneDoc]

You can use a standard parallel port BOB with the second 5I25 port (a 7I76 is extreme overkill for just adding an encoder)

Advantages of using second 5i25 port:

1. Real encoder counter, so no base thread needed (widens host PC choices since you do not need very good real time latency for just a 1 KHz servo thread )
also supports high resolution encoders

2. Only one card needed if theres no MB parallel port (say on mini-ITX MBs which have only one available PCI/PCIE slot)

Advantages of using parallel port:

1. Somewhat simpler setup ( no firmware changes)

2. if a plug-in PP is used a damaged port is a $10 replacement as opposed to a $90 replacement for a 5I25

Excellent intel PCW.. thanks.. as to the firmware, Did I see somewhere there was a version already for running 2 ports?

[SoCalPlaneDoc]

I assume that it depends on the shaft encoder. With a 1000 line encoder I think that means 2000 transitions/rev/channel. At 2000 rpm this is 67000 transitions/sec times two (A,B channels) or 133K/sec or a transition every 7.5 microseconds. That seems excessive for the PC to have to process each of them via the parallel port. (Please check my arithmetic!) On the other hand perhaps a 1000 line encoder is huge overkill just for tapping. What sort of encoder do commercial machines such as a Haas use?

As it happens, the encoder I was going to use is a 1000 - using it just because I already had it and it's meant for harsher environments:
BEI L25G-F3-1000 http://www.beisensors.com/pdfs/l25-o...al-encoder.pdf

I doubt I would ever run it over 500 rpm to tap, putting same-size pulleys on it and it's rated to run at 10K max so it should be happy when doing other machining..
I don't have any idea what HAAS uses.. every time I get close to one of the machines at work the CNC guys start to hyperventilate Don't they know Mechanical Engineers can fix problems they didn't even know they had, using methods no one understands??

[kstrauss]

I have a 770 rather than a 1100 so coupling an encoder to the spindle without significant RPM reduction limits the choices for encoders. Using something like SoCalPlaneDoc's design would be easy to mount to the pulley.

If the only use is for rigid tapping do we need an index pulse?

[brianbonedoc]

Yes you need index pulse. On my lathe I used this rotary encoder from amazon: Rotary Encoder - 1024 P/R (Quadrature) https://www.amazon.com/dp/B007R9UYZ8..._LYkXybXXNPYYA

It has a b and index signals