# Tech Setup

The following files needs to be prepared in order to set up **laygo2** 
for a new technology:

* ***\_\_init\_\_.py***: Package definition file.
* **laygo2_tech_templates.py**: Code for template definitions.
* **laygo2_tech_grids.py**: Code for grid definitions.
* **laygo2_tech.yaml**: Technology parameters used by _template.py, _grid.py files.
* **laygo2_tech.layermap**: (optional) Layer information defined by technology-speckfic PDK.
* **laygo2_tech.lyp**: (optional) Layer display information for KLayout.

A simple technology setup example for **laygo2** is available [here](https://github.com/niftylab/laygo2/tree/master/laygo2/laygo2_tech_quick_start).

Please find detailed descriptions for the listed files below:


## \_\_init\_\_.py

Contains import statements for technlogy-specific functions such as **load_templates()** and **load_grids()**.


## laygo2_tech_templates.py

This file implements technology-specific templates and their 
associated functions. It also contains the **load_template()** function 
which returns a **TemplateLibrary** object that holds template objects 
(such as MOSFETs, capacitors, and resistors) of core devices. 

The templates are typically created using predefined template classes 
such as **NativeInstanceTemplate**(for vanilla instances), 
**ParameterizedInstanceTemplate**(for PCell instances), 
or **UserDefinedTemplate**(for user-defined virtual instances),
or users can define their own template classes.


## laygo2_tech_grids.py

This file implements the technology-specific placement and routing grids 
along with their functions. The **load_grid()** function, in this file, 
returns a **GridLibrary** object which contains grid objects.


## laygo2_tech.yaml

This yaml file contains technology-specific parameters required for 
template and grid generation (such as unit resolution, pin location, 
structure size, and grid parameters).
This file serves as a central repository for all technology-related 
information for template and grid generation functions in the **laygo2_tech_template.py** and **laygo2_tech_grid.py** files.
Instead of using this yaml file, users can also hard-code the required 
the numeric parameters.


## laygo2_tech.layermap

Contains layer mapping information for the target technology.
The layer information is used for layout generation, **gds** export, and **skill** export.

The layermap file is normally provided by the technology ventor.
If the layermap file is created manually by users, please use the following format to define layer parameters.

*layername layerpurpose stream_layer_number datatype*

(please find the example layermap file in the **laygo2_tech** directiory
 for reference).