Marlin 2.0 - MKS Sbase Connectivity Issues

I'm having difficulties getting OctoPi to connect to my MKS SBase 1.3 running Marlin 2.0. Every connect attempt on all different baud rates and forcing the port end in:

Connecting to: /dev/ttyACM0
Changing monitoring state from "Offline" to "Opening serial port"
Connected to: Serial<id=0x70a465d0, open=True>(port='/dev/ttyACM0', baudrate=250000, bytesize=8, parity='N', stopbits=1, timeout=10.0, xonxoff=False, rtscts=False, dsrdtr=False), starting monitor
Changing monitoring state from "Opening serial port" to "Connecting"
Send: N0 M110 N0*125
There was a timeout while trying to connect to the printer
Changing monitoring state from "Connecting" to "Offline"
Connection closed, closing down monitor

Also tried autodetect with no luck.

lsusb -t shows:

/: Bus 01.Port 1: Dev 1, Class=root_hub, Driver=dwc_otg/1p, 480M
|__ Port 1: Dev 2, If 0, Class=Hub, Driver=hub/5p, 480M
|__ Port 1: Dev 3, If 0, Class=Vendor Specific Class, Driver=smsc95xx, 480M
|__ Port 3: Dev 5, If 0, Class=Communications, Driver=cdc_acm, 12M
|__ Port 3: Dev 5, If 1, Class=CDC Data, Driver=cdc_acm, 12M
|__ Port 3: Dev 5, If 2, Class=Mass Storage, Driver=usb-storage, 12M
|__ Port 4: Dev 4, If 1, Class=Video, Driver=uvcvideo, 480M
|__ Port 4: Dev 4, If 2, Class=Audio, Driver=snd-usb-audio, 480M
|__ Port 4: Dev 4, If 0, Class=Video, Driver=uvcvideo, 480M
|__ Port 4: Dev 4, If 3, Class=Audio, Driver=snd-usb-audio, 480M

The device id is:

Bus 001 Device 005: ID 1d50:6029 OpenMoko, Inc.

With dmesg:

[ 4.377911] cdc_acm 1-1.3:1.0: ttyACM0: USB ACM device
[ 4.378774] usbcore: registered new interface driver cdc_acm
[ 4.378783] cdc_acm: USB Abstract Control Model driver for USB modems and ISDN adapters
[ 5.198910] scsi 0:0:0:0: Direct-Access Marlin Re-ARM SDCard 01 1.0 PQ: 0 ANSI: 0 CCS
[ 5.200897] sd 0:0:0:0: [sda] 3911680 512-byte logical blocks: (2.00 GB/1.87 GiB)
[ 5.210371] sd 0:0:0:0: [sda] Write Protect is off
[ 5.210389] sd 0:0:0:0: [sda] Mode Sense: 03 00 00 00
[ 5.211171] sd 0:0:0:0: [sda] No Caching mode page found
[ 5.211198] sd 0:0:0:0: [sda] Assuming drive cache: write through
[ 5.222488] sd 0:0:0:0: Attached scsi generic sg0 type 0
[ 5.247337] sda: sda1
[ 5.255758] sd 0:0:0:0: [sda] Attached SCSI removable disk

Serial Log doesn't show much:

2018-05-24 17:40:04,119 - Changing monitoring state from "Offline" to "Detecting serial port"
2018-05-24 17:40:04,142 - Serial port list: ['/dev/ttyACM0']
2018-05-24 17:40:04,143 - Connecting to: /dev/ttyACM0
2018-05-24 17:40:04,147 - Changing monitoring state from "Detecting serial port" to "Opening serial port"
2018-05-24 17:40:04,150 - Connected to: Serial<id=0x74c50130, open=True>(port='/dev/ttyACM0', baudrate=250000, bytesize=8, parity='N', stopbits=1, timeout=10.0, xonxoff=False, rtscts=False, dsrdtr=False), starting monitor
2018-05-24 17:40:04,151 - Changing monitoring state from "Opening serial port" to "Connecting"
2018-05-24 17:40:04,170 - Send: N0 M110 N0*125
2018-05-24 17:40:34,192 - There was a timeout while trying to connect to the printer
2018-05-24 17:40:34,209 - Changing monitoring state from "Connecting" to "Offline"
2018-05-24 17:40:34,217 - Connection closed, closing down monitor

I can mount the USB drive and read from it, just cannot get Octoprint to communicate.

I flashed the latest version of OctoPi (0.15)to see if it resolved with no luck, swapped cables, the odd thing is from a Windows machine I can connect via Pronterface (while the drive is mounted), I also tried on a different Pi (both are Pi 3's)

Any suggestions on what I am missing here?

This may be this issue.

And yet, it's not like it's getting any response whatsoever from the RAMPS board.

Slightly off-topic, but I didn't realize you could even run Marlin on the SBase...though it only ran Smoothieware?

no it can run Marlin.
My second printer runs with Marlin and a sbase too.
But at this time without a display.
There is a lot of work to do.
... and the drv drivers are crap

I'm going to close this off, having tested again I can't connect from Windows anymore either (it was working on a previous revision). Rolling back to Smoothie it attaches fine.

Need to look at what changed in the Marlin 2.0 branch.......

EDIT - Looks to be this - https://github.com/MarlinFirmware/Marlin/issues/10781 (I should of checked Marlin first, sorry!!)

i maybe can check it this evening.
At the moment i only use my prusa i3 mk 2,35 clone :smiley:
i have to replace the drv with the 4988.

Do you have an SBase with stepsticks, or are you soldering?