Static RAM (SRAM)
SRAM is not in the RAM that you buy from computer store (that’s DRAM).
SRAMs are simply integrated circuits that are memory arrays with (usually) a single access port that can provide either a read or a write.
- SRAMs have a fixed access time to any datum
- As long as power is applied to SRAM, the values stored can be kept indefinitely.
- SRAMs don’t need to refresh and so the access time is very close to the cycle time is the time between memory accesses
- Typically use 6-8 transistors per bit to prevent the information from being disturbed when read
In the past, most PCs and server systems used separate SRAM chips for either their primary, secondary, or even tertiary caches. Today, thanks to Moore’s Law, all levels of caches are integrated onto the processor chip, so the market for independent SRAM chips has nearly evaporated.
RAM Is NOT implemented using Register
I actually don’t really understand how a computer works at the lowest level, which is why I should really really follow Ben Eater’s course.
“SRAM is usually implemented using a circuit of six transistors (6T) or sometimes four transistors and two resistors (4T2R) per memory cell. These circuits maintain their state as long as power is supplied, but they are not registers in the CPU sense” - ChatGPT