Third, memory term BANK: BANK refers to the calculation unit of the memory slot (also known as a memory), which is the basic operation unit of computer system and memory information exchange. Memory speed: The speed of memory is calculated by processing time consuming with memory between each CPU and the bus cycle (bus cycle) in nanosecond (NS). Memory Module: It is mentioned that the memory module refers to a plurality of memory chip chips on a printed circuit board, and this memory chip is usually a DRAM chip, but recently system design also uses it to hide the chip inlaid. The memory module is a private slot (slot) mounted on the MODULE (CHIPS) to the number of DRAM chip (CHIPs) on the MODULE, which is the main factor in the design of the DRAM chip (CHIPS) on the MODULE. . SIMM (SINGLE IN-line memory module): The number of memory ICs on the board is not equal to the following 2 types: 72PIN: 72 Foots Single-sided memory module is used to support 32-bit data processing the amount. The single-sided memory module of 30PIN: 30 foot is used to support 8-bit data processing amount. DUAL in-line memory module: (168pin) is used to support 64 bits or a wider bus, and only use 3.3 volts, usually used in a 64-bit table-on computer or server. RIMM: The RIMM module is one of the main specifications of the next generation of memory modules, which is Intel launched the memory module supported by the chipset in 1999 with a bandwidth up to 1.6GBYTE / Sec. SO-DIMM (144PIN): This is a modified DIMM module, which is smaller than the general DIMM module, applied to notebook computers, listing machines, fax machines or various Terminal, etc. PLL: For the lock circuit, used to unify the integrated pulse signal, so that the memory can access the correct access information. Rambus Memory Module (184PIN): The memory module of Direct Rdram is called RIMM module. The module has 184pin feet, the data output is serial, with the current DIMM module 168pin, and there is a large architecture. difference. 6 layers and 4 layers (6 Layers vs 4 Layers): Refers to the circuit printing board PCB Printed Circuit Board is made of 6 or 4 layers of glass fibers, usually SDRAM uses 6-layer plate, although it will increase PCB Cost but exempt noise interference, while 4 layers can reduce the cost of PCB but poor efficiency. Register: It means the cache, its function is to achieve the purpose of synchronization at high speed. SPD: The abbreviation for serial presence detect, it is a code that burned in the EEPROM. When the boot is turned on, the BIOS must detect Memory, but there is no need to detect the action, but directly read the SPD directly by the BIOS. Related information about memory.
Comparison of Parity and ECC: Parity Check Codes is widely used on an error detection code, and they add a check bits to each data, and can detect Test a character in a character (even) is wrong, but Parity has a disadvantage that when the computer finds an error, it is not possible to determine which bit of the error is not correct. Buffer and Buffer VS UnBuffer: The buffer DIMM is a method for improving the timing problem. There is no buffer DIMM, although it can be designed for the system, but it can only support four DIMM. If a buffer's DIMM is used for a host board with a speed of 100 MHz, there will be an adverse effect. The DIMM with a buffer can use four memory, but if the buffer speed is not fast enough, it will affect its performance. In other words, there is a buffer's DIMM that has slowed down, but it can support more DIMM usage. Self-Refresh: DRAM has independent and built-in charging circuitry in a certain period of time, usually used in a computer that is highly saved in a notebook computer or a portable computer. Precharge time (CAS LATENCY): Generally referred to as CL. For example, CL = 3, when the computer system reads the first data autonomous memory, the desired preparation time is 3 external chassis (System Clock). The difference between CL2 and CL3 is only necessary for the first reading data, and there is no significant effect on the performance of the entire system. Clock Signal (CLOCK): The clock signal is provided to the synchronous memory signal synchronization, and the access action of the synchronous memory must be synchronized with the clock signal. Electronic Engineering Design Development Joint Conference (JEDEC): Most of JEDEC is engaged in design, inventive manufacturing, inventive, in accordance with a group consortium composed of computer memory modules, most of the memory products produced by the general industrial, mostly established by JEDEC As an evaluation. Read-only memory ROM (ROM): ROM is only read and cannot be written to the information, because this special is the most common is the BIOS on the motherboard (basic input / output system Basic Input / Output system) Because BISO is the basic hardware setting for computer boot, it is used as a low-order communication interface with the periphery, so the BISO is burned in the ROM to avoid freely clearance. EEPROM (Electrically Erasable Programmable ROM): For a case of writing data, even if the power is turned off, it is necessary to reserve a quite long time, and if the write data does not need to increase the voltage, as long as some handle is written You can write the information into memory. ERASABLE Programmable ROM: After clearing the internal data that can be removed through the ultraviolet rays, the data can be burn into the EPROM, which is the advantage to be repeated burning information. . The read-only memory (PROM): is a memory memory, because it can only be written, so once it is written, if there is an error, it is unable to change and can no longer save other information, so As long as the memory is not available, it cannot be recycled.
Mask Rom: It is the manufacturer to produce a ROM or EPROM in advance as a sample, and then produce a large number of ROM samples, this is Mask ROM, The information burning in the Mask ROM will never be modified. Random access memory RAM (Random Access Memory): RAM is a memory that can be read and written. We also read data from RAM when writing data to RAM memory, which is different from ROM memory. However, the RAM must be stabilized by stable and smooth power, so once the power is turned off, the data in the RAM will disappear. Dynamic Random Access Memory: DRAM is the abbreviation of Dynamic Random Access Memory, is usually main memory in the computer. It is a storage action with a capacitor, but due to the problem of electricity itself, The information must be continuously accessible to other information. FPM DRAM (Fast Page Mode DRAM): is a modified DRAM, most of the 72IPN or 30PIN module, FPM is composed of memory inside the memory Pages, from 512 Bite to several kilobytes, it is characterized by waiting When you re-read, you can read the information within each of the PAGE. EDO DRAM (Extended Data Out DRAM): The access speed of EDO is about 10% faster than traditional DRAM, which is more than 72PIN, 168PIN, which is 12 to 30 times faster than FPM. SDRAM: SYNCHRONOUS DRAM is a new technique for DRAM architecture; it uses Clocks in the wafer to make the input and output can be synchronized. The so-called clock synchronization refers to the time pulse of the memory time and the CPU to synchronize access. SDRAM saves the time of executing instructions and data transmission, so that computer efficiency can be enhanced. DDR: DDR is a higher speed synchronous memory, DDR SDRAM is a DIMM module of 168PIN, which is faster than SDRAM, and DDR is designed to be a higher speed requirement such as servers, workstations, and data transmission. DDRII (Double Data Rate Synchronous Dram): DDRII is the future new standard after DDR's original SLDRAM alliance will be integrated with existing R & D results with DDR after 1199. DDRII's detailed specifications are currently not determined. DRDRAM (Direct Rambus DRAM): is one of the next-generation mainstream memory standards, which is developed by Rambus, which is connected to a common bus, which can not only reduce the volume of the controller. Increase the efficiency of data transfer. RDRAM (Rambus DRAM): It is done independently by Rambus. Its speed is about 10 times more than DRAM, although there is such a strong performance, but the memory controller needs considerable changes, so this Most of memory uses on the game machine or a professional graphics acceleration card. Vram (Video RAM): The biggest difference from DRAM is that it has two sets of output and input ports, so it can be read while reading, while outputting data. WRAM (Window Ram): It belongs to the VRAM's improvement version, which is different from its control lines with an input / output controller of twenty groups, and uses EDO's data access mode.
