Schematics for 7c81

Thanks

I just bought a programmer & Colorlite board yesterday, so might wait a couple of weeks for any more toys.

UPDATE

I made progress setting up LinuxCNC 2.9 with the 7c81 on my Spartan 6 dev board :

 

 

 

WARNING The Breakout ain't pretty



I will be abandoning this project because of a few factors :

• I received my 7i92TH's from mesa and will be focusing on connecting my custom breakout board
• The shortage of  SN74CBT16211 as to using the 74 254 for a more specific breakout
• Cost as JLCPCB as a min of 5 PCB to order.

 

I've just got the 7c81 firmware running on a Mimas Spartan-6 dev board. Got some let over breakout boards I used when I was running MK on a BeagleBone Black, so the 5v/3v3 translation isn't an issue.
Just over the weekend I ordered the dev board you linked to earlier.
Current setup for experimentation.

Which level shift IC are you going to use ? What tipe of CNC are you building ?

First of I'd like to give a thank you to yourself for the inspiration and Pete from Mesa for the help.
Price wise and ease of use I'd go for the Mesa products. ATM for various reasons it's not an option. Plus I like having a tinker.

Inputs I'm using a 75LVC245 Outputs are either 74HCT540 or 74HCT541. This is going to be for my Myford ML7/Super 7 Frankenstein. Built from completely part by part from mostly ebay. Fasteners, shaft keys and misc stuff was bought brand new. So far the Z axis is done, X axis is going to require some deep thought..

Actually going to use this for level shifting, have plenty of parts and boards in one of the many useful boxes.
github.com/ozzyrob/pp_bob_input
There's a "sister board" as well.
github.com/ozzyrob/pp_bob_output
There's a mistake with both boards as the 26 pin headers don't follow the standard for hooking up directly to a printer port . But being all through hole parts it's not such an issue.

I've used these boards when I was using a BeagleBoneBlack for the mill with Machinekit. I've also used them when I was testing the Linuxcnc-RIO project that uses the Lattice ICE40 fpgas.



Have a "full Mesa setup" for the mill.

Further to my adventures with the Omdazz Spartan 6 dev board as discussed in this thread I've been designing a interface board to make life a little easier.

• It uses SN74CBT3245DBQ to perform level shifting, zener used to provide 4.2v voltage.
• 2 DB25 connectors which can be used with generic Parallel Port BoBs or MESA DB25 daughter boards (I recommend genuine Mesa products, but my situation pushes me this way forward).
• 6 extra I\Os on a 2x5 pin header includes 2xGND 2x5v (smart serial ports or whatever).So essentially 40 pins to use.
• Through hole components except for ICs.
• Pictures tell 1000 words, board is reasonably labeled IMHO.Still need to design another board to use the 32 other pins that 7i90HD allows (72 pins all up), and for the SPI connection.  
  
  
  

I don't know your application but maybe consider using these connections :

 

If your board is gonna be in a vibrating environment this is a must.

I'm not in the habit of mounting the electronics to the machine itself. So unless there's gunna be an earthquake in Sydney....