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[ried]

I've been experimenting with various combinations of hardware and software to enable BLU's built-in serial communication / file transfer capability between Lisa and modern Mac hardware, like a MacBook Pro. So far, I have been successful with the Lisa 2/10 across the following configurations:

System #1:
   Late 2013 13” MacBook Pro (Intel, macOS Big Sur 11.7.10)
Software:
   CoolTerm.
Lisa is connected to:
   C2G 6’ DB25 Male to DB9 Female Serial RS232 Null Modem Cable.
   Gearmo USB to Serial RS-232 Adapter with LED Indicators, FTDI chip
   or
   Sabrent CB-DB9P USB 2.0 To Serial DB9 Male (9 Pin) RS232 Cable Adapter, Prolific chip
Note: Flow Control = DTR on, CTS off.

System #2:
   Late 2020 13” MacBook Pro (Apple Silicon, macOS Sequoia 15.1.1)
Software:
   CoolTerm.
Lisa connected via:
   C2G 6’ DB25 Male to DB9 Female Serial RS232 Null Modem Cable
   Sabrent CB-DB9P USB 2.0 To Serial DB9 Male (9 Pin) RS232 Cable Adapter, Prolific chip
   USB-A to USB-C adapter
Note: Flow Control = DTR on, CTS off.

I have also been experimenting with another macOS app called Serial and text communication seems to be working, but file transfers do not. I have asked the developer for more information.

I have not yet found a working combination for Lisa 1/5 machines, but I am working on that also. Seems to be related to pin 4 (RTS) where the Lisa 2/10 features a 10k pull-up resistor and the Lisa 1/5 does not, or null modem wiring (TBC).

Hopefully this info helps someone with a Lisa 2/10 (or Mac XL) that wants to use BLU's built-in serial communication capability. Special thanks to sigma7 for creating that software, and for continuously providing his insight while I continue looking for solutions.

For reference, here's a screenshot of CoolTerm's working serial port configuration:

[ried]

Does anyone have a working configuration that enables a Lisa 1/5 running BLU to communicate with a modern Mac via serial to USB adapter? I am having a devil of a time trying to figure one out. The Lisa 2/10 was comparatively easy.

It's so frustrating that I might end up using Windows 

[Lisa2]

OK, I just tried using BLU V0.9 on a Lisa2/5 ( port B ) connected to my M1 Mac Mini running MacOS Monterey and CoolTerm 2.3.0.  I have a FTDI based USB to serial adapter.  It all worked straight out the box, I started CoolTerm, picked my port and set it 56K baud.  Are you trying to say this may be  a specific issue with a Twiggy Lisa?
Rick

[ried]

That's amazing. Can you please share your specific make & model of FTDI-based USB to serial adapter? Which null modem cable (or other DB25 to DE-9 adapters) are you using? The more detail you have on the exact hardware you're using, the better. Thank you!

[AlexTheCat123]

I'm also able to connect with my 2/5s without any issue. I use Serial instead of CoolTerm, and everything works fine (including file transfers), so I'm not sure what's causing your issues there. I'm out of town right now, but I can get you more info on my USB to serial adapter once I get back!

[Lisa2]

Can you please share your specific make & model of FTDI-based USB to serial adapter? Which null modem cable (or other DB25 to DE-9 adapters) are you using?

The USB adapter I used is a USO9ML2-LS made by B&B Electronics (now Advantech):

https://www.advantech.com/en-us/products/b851dad7-5f2f-46da-926d-6fe3157b34aa/bb-uso9ml2-ls-a/mod_3aa59323-fad3-4a62-bc81-47d4c4ce2511

Note that this adapter has some extra features not required to communicate with Lisa such as isolation and a locked serial number.  It does use FTDI chipset, something I prefer over the prolific adapters.

My cable is exactly as recommended in the BLU manual, Appendix B:

Lisa       Signals     PC
DB25M                DE9F
  2     Tx > Rx        2
  3     Rx < Tx        3
  7         Gnd          5
  6    DSR < RTS     7
 20    DTR > CTS    8

[ried]

I'm also able to connect with my 2/5s without any issue. I use Serial instead of CoolTerm, and everything works fine (including file transfers), so I'm not sure what's causing your issues there. I'm out of town right now, but I can get you more info on my USB to serial adapter once I get back!

Two issues with Serial here:

• When I use Serial to receive an xmodem transfer, it comes to the Mac as a text file, i.e. "Received_File.txt" and not as a raw data file. There does not seem to be a raw data handling setting in the Serial app. Please let me know if you have found otherwise.
• When Lisa does send the file via xmodem transfer, the Serial app does not seem to close the transfer and save the file when the Lisa has finished sending. It continues to receive and wait for more data, and my only option is to cancel - rather than save what has been sent.

Can you please share your specific make & model of FTDI-based USB to serial adapter? Which null modem cable (or other DB25 to DE-9 adapters) are you using?

The USB adapter I used is a USO9ML2-LS made by B&B Electronics (now Advantech):

https://www.advantech.com/en-us/products/b851dad7-5f2f-46da-926d-6fe3157b34aa/bb-uso9ml2-ls-a/mod_3aa59323-fad3-4a62-bc81-47d4c4ce2511

That is very helpful. I suspect we have found the difference between a $10-30 adapter and a $150 adapter   I shall change out the adapter and report back. Thank you both very much.

[Lisa2]

I’m glad this topic came up.  I’ve been a coolterm user for sometime, but I did not know they added xmodem support recently. 
To tell the truth, the last BLU project I worked on, I had to use Windows (teraterm) because I didn’t know coolterm  had xmodem support.
Rick

[ried]

Further investigation indicates that the Serial B traces are damaged on the 2/5 motherboards - likely due to battery corrosion from long ago. I have tried multiple (known good) I/O boards, but the result is the same. Now we know.