FPGA Controller for LED Matrix
From Fixme.ch
A FPGA-based interface controller for
Limpkin's RGB LED matrices.
Matrix reference
Overview
- FPGA drives 1 or more (up to 4?) matrices
- use block ram or external SRAM for frame buffer storage
- interface with PC
Feature ideas
- double buffering
- larger off-screen buffer + compositing ops?
- character generation
- update only sections
- small CPU core to execute short programs?
Components
Memory
External SRAM needs to be fast enough to handle all reads during one cycle. Per connected matrix we need to read 6 bytes per cycle. Clearly this would require use to run at 150MHz, which is infeasible. If we use a separate chip per matrix block (6 chips or 3 chips with 16bit width), we can still operate with 25MHz.
Concurrent writes need to be possible, but at a lower speed. Either buffer reads and slip in writes when there is slack (complicated), or alternate between reads and writes at higher speed (DDR?).
