This assignment is about to make the FabISP in-circuit programmer. The FabISP is an in-system programmer for AVR microcontrollers. That allows you to program the microcontrollers on other boards using a USB cable and 6-pin IDC to 6-pin IDC cable. We will be using these programmers through the semester to program the other boards we create
Tools:
Roland Modela MDX-20
1/64" (engravement) and 1/32" (cutting) endmills.
Doble sided tape
Screwdriver/p>
Download the milling files of hello.ISP.44 here:
Steps:
//Milling the board
For milling the board we are using the Roland Modela MDX-20 and the Fab Modules
/Make sure you have a sacrificial board underneath the board that you are milling
/Glue the board in the milling machine with double sided tape to keep the model from moving in the milling machine and loosing the 0,0 poin
/Power on Modela machine and press the “View Button” to set the default 0,0 position
/Set up the 1/64 n-mill with the set screws on the machine,as close to the copper as possible without touching it, by keeping the down button pressed.To mill out the traces of a circuit board we usually need 1/64" n-mill
/Open Fab Modules on terminal
/On the new window select the endmill settings as 1/64".
/Set the x,y 0,0 at the bottom-left corner by changing the values in the Fab module window
/Set the z origin:Loosen the set screws and push the bit all the way onto the copper. Tighten the screws
/Set offset of 6
/Click on the “load button” and select your file(hello.ISP.44.traces.png)
/Click on the “make path button”.
/Click "make RML"
/Click "send"
/For cutting the board we usually need 1/32th n-mill
/Change the drill tool to the 1/32" on the Mondela
/Select the endmill settings as 1/32"
/Set the z origin:Loosen the set screws and push the bit all the way onto the copper. Tighten the screws
/Set offset of 2
/Click on the “load button” and select your file(hello.ISP.44.interior.png)
/Click on the “make path button”
/Click "make RML"
/Click "send"
/Click "begin milling"
//Soldering the board
/Fab ISP board components:
PCB, copper plate
ATiny44 micro controller
Resistors| 2x 0.0 Ohm ,1x 1K,1x 10K,1x 499 Ohm,2x 100 Ohms
Capacitors| 1x 1uF,2x 10pF
Cristal 20MHz
USB connector
6 Pin conn male
Diodes| 2x 3.3 V Zener
Download the FabISP labeled board diagram
so that you can see where to place the components on the board
/Solder the components to the board using a soldering iron and solder
TIPS:
|It is helpful if you solder the components ftom inside to the outside, starting with the microcontroler
|There is a little circle on the microcontroler that should be facing to the top left if your board is oriented in the same direction as the FabISP labeled board diagram
, where the VCC is|Crystal(20 MHz) do not have polarity, orientation does not matter.
|Diodes have polarity. The "C" or cathode that is marked on the diagram, is marked with a tiny line on the component
|Resistors(R1, R2, etc) and capasitors(C1, C2, etc) do not have polarity, orientation does not matter
|The components marked as SJ1 and SJ2 are solder jumpers. Solder 0 ohm resistors at these points
|The orientation in the 6 pin header(J1 ISP) does not matter
//Check the connections with the multimeter to make sure that power and ground are not connected and there is not a short on the power line.
//Do the "smoke test". Plug the FabISP into your computer via the mini USB cable. Install the necessary software for AVR programming
//Programming the ATtiny44(make hex, make fuse, make program)
//Unplug the programming cable, remove power, and desolder the jumper SJ2
//Using the FabISP to program other microcontrollers
