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Simple ZMODEM server for RaSCSI

Skate323k137

Well-known member
Working with my new RaSCSI, and ran into some issues with the Daynaport setup. Open transport doesn't recognize my CPU upgrade, and MacTCP is only working outbound, so I set that aside (I'll get back to it), because honestly, all I really needed was the ability to access an FTP server, HTTP server, or any unencrypted file share that doesn't involve copying whole disk images to an emulator, or mounting disk images on the RaSCSI, etc.

While this is basically a functional POC at 9600bps, I originally shot for 14400, but it was not liked during compiling. I can try some other faster values, but the project I forked defaulted to 115200 which I think would cause packet loss on my SE. With a wimodem232 19200 is usually the sweet spot, I may try that tomorrow.

Right now, I am connecting the SE to the RaSCSI with a Null Modem cable and Serial to USB cable (pretty standard, null modem cable from retrofloppy). Instead of binding this to /dev/ttyUSB0, It would be more fun to make a socket on the rascsi that's accessible over IP, and connect to that from a WiModem232, but perhaps that's an exercise for another day.

In short: You need a RaSCSI, null modem cable, and serial to USB adapter. I am using zterm on my mac (confusing, as the git I forked is called zterm, but I'll get to renaming later).

To set this up (if I remember right, getting late) on an up to date RaSCSI, ssh as pi to the RaSCSI and:
Code:
sudo apt-get install cmake lrzsz
cd /home/pi/
mkdir /home/pi/zterm_public
git clone https://github.com/Alex-Kw/zterm
cd build
ln -s /home/pi/zterm_public zdata
cmake ..
make

With any luck it's set up, from the build directory (which you should still be in) run ./zterm and you should have a daemon. Place files you want accessible from the Mac in the /home/pi/zterm_public/ directory.

The commands are listed at https://github.com/Alex-Kw/zterm but it's basically zdir to list files, zsend (file) to request a file, and CLIENT to close connection.

 

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Skate323k137

Well-known member
So I actually have this working over wifi now with a WiModem232.

I'm not sure if anyone else will find this useful at all, but it was fun. I'm still going to try to up the baud rate.

In short this is using socat to create 2 linked virtual serial interfaces on the RaSCSI. Then it uses ser2net to bind one of those to an outside port, and zmodem daemon bound to the other.

With this setup you can access a simple download only file share on the RaSCSI from any computer with a serial port, or any computer that uses a wimodem232.

Obviously using disk images is infinitely faster, in this case, I can move small files without mounting or unmounting any images, and without shutting down the Mac. Since the daynaport stuff isn't working out for me yet, the RaSCSI is just a convenient Debian like box to run this on.
 

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Skate323k137

Well-known member
I'm probably about near the end of this exercise. I was able to get 19200 baud set up, but in practicality, it's too slow to really use for much.

Both on null modem cable and over wifi/wimodem232 connected to the RaSCSI via wifi on the LAN, the speed is a whopping ~1800 BPS :ROFLMAO:
 
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