NOR Flash: Difference between revisions
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<li>When NOR is run in parallel it allows for one-byte random access which means instructions can be taken and run directly from the chip simple to how RAM functions</br> | <li>When NOR is run in parallel it allows for one-byte random access which means instructions can be taken and run directly from the chip simple to how RAM functions</br> | ||
hence why NOR has uses a static random-access memory(SRAM)interface that includes an address pins to map to every part of the chip, which allows access to every byte stored on the chip.</br> | hence why NOR has uses a static random-access memory(SRAM)interface that includes an address pins to map to every part of the chip, which allows access to every byte stored on the chip.</br> | ||
However, this means that NOR has to write in larger chunks than NAND which ultimately reduces the speed of the chip and its lifetime as a larger area is worn through use.</li> | However, this means that NOR has to write in larger chunks than NAND, which ultimately reduces the speed of the chip and its lifetime as a larger area is worn through use.</li> | ||
<li>NOR is typically used for tasks such as code execution due to its SRAM function, however this does make it more expensive to produce (per bit) whereas NAND lacks SRAM so is typically used for data storage</li> | <li>NOR is typically used for tasks such as code execution due to its SRAM function, however this does make it more expensive to produce (per bit) whereas NAND lacks SRAM so is typically used for data storage</li> | ||
<li>Initially, NOR requires a higher power draw upon start up but requires less power during operation than NAND typically would.</li> | <li>Initially, NOR requires a higher power draw upon start up but requires less power during operation than NAND typically would.</li> | ||
<li>NOR is typically used to storage an embedded device firmware due to its higher read performance when compared with NAND</li> | <li>NOR is typically used to storage an embedded device firmware due to its higher read performance when compared with NAND</li> | ||
<ul> | <ul> | ||
<h2> | <h2> Serial NOR and Parallel NOR </h2> | ||
<h3> Serial NOR </h3> | |||
Serial NOR typically communicates over a serial protocol(3 to 4 wires) whereas Parallel uses one wire for every part of the chip</br> | |||
This means that Serial transfer one bit at a time whereas Parallel can transmit multiple bits at once(8 wires, means at bits/one byte at once).</br> | |||
Due to the simpler connection scheme, serial NOR is typically cheaper and simpler to produce as well as saving space on the PCB where there isn't much space</br> | |||
It also tends to draw less power than Parallel, all these factors considered makes it a good candidate for small low powered devices, such as IOT and mobile devices.</li> | |||
<h3> Parallel NOR </h3> | |||
</p> | |||
<h1 id="section0">What tools you will need</h1> | <h1 id="section0">What tools you will need</h1> | ||
<i> Items are not listed in any particular order </i> | <i> Items are not listed in any particular order </i> | ||
Revision as of 12:09, 20 February 2025
Contents
Background information
NOR flash is completely different to NAND in the fact that it uses NOR gates instead of NOT and AND gates like NAND does.
Difference in NOR and NAND
- NOR has a faster read speed,were as NAND has a faster write and erase speed.
- NOR is more expensive
- NAND has a higher capacity than NOR
- NOR can be run in parallel and in series, Where as NAND runs in series meaning it can wire 8 bits of data one e.g one byte at a time(8 bits = 1 byte)
- When NOR is run in parallel it allows for one-byte random access which means instructions can be taken and run directly from the chip simple to how RAM functions
hence why NOR has uses a static random-access memory(SRAM)interface that includes an address pins to map to every part of the chip, which allows access to every byte stored on the chip.
However, this means that NOR has to write in larger chunks than NAND, which ultimately reduces the speed of the chip and its lifetime as a larger area is worn through use. - NOR is typically used for tasks such as code execution due to its SRAM function, however this does make it more expensive to produce (per bit) whereas NAND lacks SRAM so is typically used for data storage
- Initially, NOR requires a higher power draw upon start up but requires less power during operation than NAND typically would.
- NOR is typically used to storage an embedded device firmware due to its higher read performance when compared with NAND
- Test
- Test
- 1.test
- 2.test
- 3.test
- Reference 1: Source details
- Reference 2: Source details
Serial NOR and Parallel NOR
Serial NOR
Serial NOR typically communicates over a serial protocol(3 to 4 wires) whereas Parallel uses one wire for every part of the chipThis means that Serial transfer one bit at a time whereas Parallel can transmit multiple bits at once(8 wires, means at bits/one byte at once).
Due to the simpler connection scheme, serial NOR is typically cheaper and simpler to produce as well as saving space on the PCB where there isn't much space
It also tends to draw less power than Parallel, all these factors considered makes it a good candidate for small low powered devices, such as IOT and mobile devices.
Parallel NOR
What tools you will need
Items are not listed in any particular orderRequired
Optional but useful
Uses of this skill
Step-by-step guide with images
Insert step-by-step walkthrough with images and summary text here
Flow chart of order of operations
Insert a flow chart of steps and actions for each task (create using diagram)
Troubleshooting/tips and tricks
Fixes to any common issues that were encountered or could be easily encountered
Related Topics
Topics such as desoldering to chip off or firmware dumping for disk PCB repairs
Further reading
External references in wiki references can just be cited through the keyword link