README

# GPIO Hardware Module

## Summary

This folder contains the SystemC hardware description for a GPIO Hardware Module that is Wishbone compatible.


## Configuration Options for ParaNut

There are configuration options in the config.mk files at the root of the project and in the system/refdesign/hardware/boards/[boardname]/config.mk.

Available configuration options:

* CFG_GPIO_ENABLE: Enables the Synthesis of the GPIO Module
* CFG_GPIO_BASE_ADDRESS: Sets the base address of the UART Module in the ParaNuts address space
* CFG_GPIO_AMOUNT: Sets the amount of GPIO Pins beeing created only 8 is currently supported by the hardware constraint file
* CFG_GPIO_OUTAMOUNT: Sets the amount of Output Pins for the GPIO Module, a maximum of 8 is supported at the moment, the rest of the CFG_GPIO_AMOUNT ist set as Input Pins

## Configuration of the GPIO Hardware Register

The Register of the GPIO Module is 32 bit wide to support the whisbone data in, only 8 bits of this regiser are beeing used at the moment
bit 0 to CFG_GPIO_OUTAMOUNT-1 are beeing used as the bits to set the output pins high or low and are readable and writeable bit CFG_GPIO_OUTAMOUNT to CFG_GPIO_AMOUNT are beeing used for Input Pins this part of the register is readable only and cannot be set by a write command

## Testbenches

The testbenches for this GPIO Module can be found in the folder tb/gpio.

To run them use the following command:

```sh
make run
```

## High Level Synthesis

This is a manual on how to do high level synthesis for the GPIO module

### Installing the Prerequisites:

#### ICSC:

1. Follow the instructions found here [ICSC](https://github.com/intel/systemc-compiler/wiki/Getting-started)
2. Write the ICSC_HOME Environment Variable to your .bashrc
**Important:** don't add the setenv.sh to your .bashrc otherwise the ParaNut won't work correctly

#### sv2:
1. Download the current version of the sv2v tool from the following link:         [sv2v](https://github.com/zachjs/sv2v/releases/tag/v0.0.10)
2. Unzip the Package and add the Folder that is containing the sv2v executable to your PATH variable

### Running High Level Synthesis:

Run the following command:

```sh
make update_gpio
```

**Important:** This Command needs to be run in a console where the settings64.sh of Vivado is not sourced

### For Further Information on the GPIO Module:
Further information about the workings of the GPIO Module can be found in the */\<ParanutDirectory\>/sw/lib_gpio_api/README* and the */\<ParanutDirectory\>/sw/lib_gpio_api/libgpio_example/README*