Suppose I have 512 leds in a 16 by 32 grid. I want to control what is displayed on the grid.
To do this suppose I have a timer counter that is constantly counting between 0 and 31 in binary. This timer is hooked up to 2 things. The first is a decoder so that one column of the LEDs is "activated".
The second is a kind or RAM (I don't know what to call it), which has 16 bit words and 64 addresses. The timer is hooked up to the bottom 5 bits of the addressing system of the ram, and the LED grid is hooked up to the outputs.
The Micro controller is then hooked up to the top address bit so that this system can have two separate memories to grab data. One is active while the micro writes to the other memory locations.
Here is a simplified schematic (obviously I will have transistors and what not where needed):
My question is: What can I use for the RAM memory? And what is it called?
Some requirements:
- Can be read at 32kHz
- Has at least 64 words with a word size of at least 16 bits
- Can be writable while still reading other memory addresses