ad485x_fmcz/zed: Add README

Author: StancaPop

projects/ad485x_fmcz/zed/README.md

@@ -0,0 +1,76 @@
+# AD485X-FMCZ/Zed HDL Project
+
+## Building the project
+
+The parameters configurable through the `make` command, can be found below, as well as in the **system_project.tcl** file; it contains the default configuration.
+
+```
+cd projects/ad485x/zed
+make
+```
+
+The overwritable parameters from the environment are:
+
+- LVDS_CMOS_N - selects the interface type to be used:
+  - 0 - CMOS interface (default)
+  - 1 - LVDS interface
+  
+- THREE_W_SPI - selects the SPI configuration to be used:
+  - 0 - 4 wire SPI (default)
+  - 1 - 3 wire SPI
+  
+- DEVICE - selects the device to be used:
+  - AD4851
+  - AD4852 
+  - AD4853
+  - AD4854 
+  - AD4855
+  - AD4856 
+  - AD4857
+  - AD4858 (default)
+
+### Example configurations
+
+#### Configuration using CMOS interface, 4 wire SPI (default)
+
+Connect the evaluation board FMC to the FMC connector of Zedboard.
+
+This specific command is equivalent to running "make" only:
+
+```
+make LVDS_CMOS_N=0 THREE_W_SPI=0
+```
+
+#### Configurations using LVDS interface
+
+To build the LVDS interface - 4 wire SPI:
+
+```
+make LVDS_CMOS_N=1 THREE_W_SPI=0
+```
+
+To build the LVDS interface - 3 wire SPI:
+
+```
+make LVDS_CMOS_N=1 THREE_W_SPI=1
+```
+
+#### Configurations using LVDS interface
+
+To build a specific part configuration:
+
+```
+make DEVICE=AD4851
+```
+
+Corresponding device trees:
+
+- [zynq-zed-adv7511-ad4851-fmcz.dts](https://github.com/analogdevicesinc/linux/blob/main/arch/arm/boot/dts/zynq-zed-adv7511-ad4851-fmcz.dts)
+- [zynq-zed-adv7511-ad4852-fmcz.dts](https://github.com/analogdevicesinc/linux/blob/main/arch/arm/boot/dts/zynq-zed-adv7511-ad4852-fmcz.dts)
+- [zynq-zed-adv7511-ad4853-fmcz.dts](https://github.com/analogdevicesinc/linux/blob/main/arch/arm/boot/dts/zynq-zed-adv7511-ad4853-fmcz.dts)
+- [zynq-zed-adv7511-ad4854-fmcz.dts](https://github.com/analogdevicesinc/linux/blob/main/arch/arm/boot/dts/zynq-zed-adv7511-ad4854-fmcz.dts)
+- [zynq-zed-adv7511-ad4855-fmcz.dts](https://github.com/analogdevicesinc/linux/blob/main/arch/arm/boot/dts/zynq-zed-adv7511-ad4855-fmcz.dts)
+- [zynq-zed-adv7511-ad4856-fmcz.dts](https://github.com/analogdevicesinc/linux/blob/main/arch/arm/boot/dts/zynq-zed-adv7511-ad4856-fmcz.dts)
+- [zynq-zed-adv7511-ad4857-fmcz.dts](https://github.com/analogdevicesinc/linux/blob/main/arch/arm/boot/dts/zynq-zed-adv7511-ad4857-fmcz.dts)
+- [zynq-zed-adv7511-ad4858-fmcz.dts](https://github.com/analogdevicesinc/linux/blob/main/arch/arm/boot/dts/zynq-zed-adv7511-ad4858-fmcz.dts)
+