The Einstart S is a commercial machine that ships with a proprietary firmware and "licensed" slicer program which requires the original SD card or license file (.lic/.reg) from support in order to function. The impetus for the port was that I acquired the machine on the weekend when tech support was closed.
## Specifications:
- Powder coated, formed steel enclosure
- Machined Aluminum internal axis support frame
- Genuine matched HIWIN rails on all axis
- Genuine Minebea NEMA17 motors (200 steps/rev)
- THC7128 3A Stepper Drivers (configured for 16 microsteps, loud)
This machine probably doesn't ship with the arduino boot loader, so unless you reflow a 2560 on there to replace the atmega1280 like I did (to preserve the original firmware), you'll need to use ISP to do an initial firmware load and/or bootloader flash!
It's not that bad though, you can just buy an ISP programmer with the appropriate header, or build an ISP programmer using the Arduino ISP sketch (wiring is easier if you use the "old style wiring" which utilizes the following pinout: (see the comments in the ArduinoISP sketch).
I used an arduino Nano and a header I had lying around, but you could do the same with a nano and some dupont headers cut and soldered to the board, and taped/glued into a header.
Triple check your pinouts, it shouldn't fry if connected backwards but if your pinout is wrong you're going to struggle for sure.
#### ArduinoISP Sketch pinout for 10pin ISP header using "old style wiring":
See the comments in the ArduinoISP sketch under File:Examples:ArduinoISP
1 MOSI D11
2 5v Vcc
3 N/C
4 GND
5 RES D10
6 N/C
7 SCK D13
8 N/C
9 MISO D12
10 GND GND
#### Einstart Motherboard ISP Header Pinout
The 10 pin ISP Header is located to the right of the ATMEGA chip, just above the long LCD header.
## Uploading Marlin firmware to a stock Einstart S
### Summary:
Make, buy or steal a 10 pin ISP programmer and select the appropriate programmer option via Tools:Programmer in Arduino IDE, use the Sketch:Upload Using Programmer command or Shift-Ctrl-U (vs Ctrl-U to upload via serial).
### Detailed procedure:
You can either load Marlin directly via ISP programmer (easiest, but requires opening the chassis every time you want to change/update firmware) or, just program the bootloader which will enable later uploads via USB. HOWEVER, to actually upload the sketch you will need one of the following:
- Install bootloader on atmega1280 to enable native USB uploads (also requires ISP).
- AND
- Connect button between RESET and GND on ISP header, release post compile just before upload starts.
- OR
- Install permanent modification described below, requires no button press during upload.
### Permanent modification to enable USB uploads via Arduino IDE
As a permanent modification to enable direct USB upload from the arduino IDE, you would need to flash the boot loader using ISP first; but then you can solder a wire or 100n capacaitor between the DTR line on the FTDI to the reset line, which is conveniently located in several places on the board.
#### FTDI Chip Diagram (IC1)
______
TXD --|1 28|--OSCO
DTR --|2 27|--OSCI
RTS --|3 26|--TEST
VCCIO--|4 25|--AGND
RXD --|5 24|--N/C
RI --|6 23|--CBUS0
GND --|7 22|--CBUS1
N/C --|8 21|--GND
DSR --|9 20|--Vcc
DCD --|10 19|--RES
CTS --|11 18|--GND
CBUS4--|12 17|--3V3
CBUS2--|13 16|--USBDM
CBUS3--|14 15|--USBDP
|______|
#### Arduino Reset Circuit
DTR-----||----GND----/\/\/\/----Vcc
100nf 10k
With this modification you no longer need the reset button and you can program directly from the Arduino IDE.
### Power notes during flashing.
You do NOT need power connected when flashing via ISP.
You DO need power when flashing via USB Serial but you MUST time the release of the reset line to allow the upload unless you've performed the permanent modification.
