ZX-Badaloc Reloaded
Implementing the ZX-Badaloc Clone into an FPGA
The VGA output of the Xilinx Spartan 3E board can only show 8 colors. In order to display the 16 colors available on ZX-Spectrum with the 'Brightness' attribute, a small modification is required.
Resistors R3, R5 and R7 (270 ohm) should be replaced by 330 ohm. These are '0402' smd type, but the bigger '0603' will fit as well and are easier to handle. This picture shows the location of the three resistors on the back side of the Xilinx board. The wires coming from the hirose connector are also visible here (resistors are just below the wires):
Pins 34, 36 and 38 of the HIROSE connector (the 100 pin one) should be connected to pin 1, 2 and 3 of VGA output respectively, by three 2,2K resistors. These can be of any size (0402, 0603 or even 0805). This picture shows the exact location of the pins; resistors used are 2,2K, 0805 smd type:
