I use PC817, just like in the first post under "parts list". I got mine from an old PSU.
 
For DDR4 you'll only need one optocoupler. SA1_CTL is for DDR3/DDR2 and modules with "_OPT" suffix will never be needed. (The schematic was created before DDR5 specs were publicly available and were included only for future-proofing, but as it turned out, they won't be ever needed.)

New version after a lengthy break: 20220614
 

GUI

• Fixed: Connect button dropdown arrow is hidden when no device is connected
• Added: Tooltips to some items in the Settings window

SMBus

• Added: AMD AM4, AM1/FS1b, FM1, FM2, and FM2+ support *

* This release should also work with AMD X399 and TRX40 based systems, but it hasn't been tested. If you have any of such systems, please test it and report bugs if you find any.

nice to see your still making updates

New update: 20220628
 

GUI

• Enhancement: Set RSWP option can be used to toggle or clear RSWP
• Fixed: DDR5 SPD product information and CRC support

 
Previous versions with preliminary DDR5 support relied on proposed Jedec's JESD400-5 document revision 0.89 and 0.90 dated January 2020 floating around. Final specification is not publicly leaked, but based on the Micron's DDR5 SPD documents and several other commercially available DDR5 SPD dumps I've been able to acquire, checksummed data and checksum locations differ from the original outdated Jedec's proposed SPD contents. This release will work properly with DDR5 CRC checksums.

New version with some fixes, enhancements, and more platform support: 20220802
 

GUI

• Fixed: Crash occurring after writing SPDs with Arduino when program is run as normal user
• Improved: Arduino firmware wizard opens destination directory contents in explorer
• Improved: Arduino firmware wizard handles directory and file permission errors
• Improved: Idle performance during open device selection dialog window
• Updated: Manufacturer’s ID codes database (ref. JEP106BE, Jan 2022)

SMBus

• Added: Nvidia nForce & MCP support *

Supported chipsets: Nforce2, Nforce3, Nforce4, MCP51, MCP55, MCP61, MCP65, MCP67, MCP73, MCP78S, and MCP79. Nforce and MCP89 are not supported.

New version with some fixes and improvements: 20220806
 

GUI

• Fixed: Crash when opening files by dragging them onto program icon
• Improved: Manufacturer name lookup performance
• Added: Thaiphoon Burner file (*.thp) support

SMBus

• Fixed: SPD writing on Nvidia based platforms

CLI

• Fixed: Compatibility with the latest DLL

 
 

No new version yet, but here's a preview of one of the features I'm currently working on.
 
This will add (requested and expected) editing capabilities, like in thousands of other hex editors out there.
 

 
 
 
 

great stuff

Hotfix: 20221026

• Fixed: Freeze issues when virtual or Bluetooth COM ports are present

This fixes GUI and CLI freezing issues when virtual or Bluetooth COM ports are present.
This release is marked as pre-release because it contains an updated dll only. To use, extract the archive into directory where you have v.20220806 located, overwriting the old file.
 
Full release with updated editor will be posted when it is ready.

Finally, a new version after weeks of lengthy development: 20221111

GUI

• Fixed: Write protection check accuracy before writing when multiple devices are present on the same bus
• Fixed: Delay when opening EEPROM menu when Arduino auto connect option is enabled
• Updated: Thaiphoon Burner DDR5 & DDR4 file (*.thp) import support (TH52, TH42)
• Updated: Manufacturer’s ID codes database (ref. JEP106BF.01, October 27, 2022)
• Fixed: High idle CPU usage when Arduino auto connect option is enabled
• Fixed: Freeze issues when virtual or Bluetooth COM ports are present
• Improved significantly: Manufacturer name lookup performance
• Added: Opacity effects when moving windows
• Added: Data copy formats
• Added: Data editor

CLI

• Updated: Compatibility

Firmware

• Added: Background I2C monitor

 
Apart from bugfixes and performance improvements, this release adds the most anticipated feature - the data editor.
 
The editor component had to be written from scratch, because there's no such control provided out of the box included with .NET framework. While there are a couple of third-party open source editors available, none have features I needed and are bloated with options that aren't necessary, so I wrote my own editor. Initially, I went the lazy route and used a bunch of text boxes to display each byte, but it turned out to be a performance nightmare, so the initial implementation was destined to be doomed. And I made the right decision to scrap the original code and start from scratch, but in the end it was worth the effort.
 
Editor features in no particular order:

• Inline Hex editor:
  
• Inline ASCII editor
  
• Undo/redo capabilities
• Navigation with arrow keys, pgup/pgdn keys, and home/end keys; scrolling follows cursor
• Individual byte and bits editor:
  
  
• Color coded states:
  
  • Normal data - black text
  • Unsaved data - red text
  • Redoable data - blue text
  • Active/inactive panel - white/grey background, respectively
  • Similar bytes - light blue background (disabled by default)

 
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