“EEPROM:update()”的版本间的差异
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(以“:EEPROM {| border="0" cellpadding="20" width="100%" |- |width="100%" valign="top" align="left"| <font color="olivedrab" size="+3">'''update()'''</font...”为内容创建页面) |
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<font color="orange" size="+1">'''描述'''</font> | <font color="orange" size="+1">'''描述'''</font> | ||
| − | + | Write a byte to the EEPROM. The value is written only if differs from the one already saved at the same address. | |
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| − | + | <font color="orange" size="+1">'''语法'''</font> | |
| − | + | EEPROM.update(address, value) | |
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| − | <font color="orange" size="+1">''' | + | <font color="orange" size="+1">''' 参数'''</font> |
| − | the | + | address: the location to write to, starting from 0 (int) |
| − | <font color="orange" size="+1">''' | + | value: the value to write, from 0 to 255 (byte) |
| + | |||
| + | |||
| + | <font color="orange" size="+1">''' 返回值'''</font> | ||
| + | |||
| + | none | ||
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| + | <font color="orange" size="+1">'''注意'''</font> | ||
| + | |||
| + | An EEPROM write takes 3.3 ms to complete. The EEPROM memory has a specified life of 100,000 write/erase cycles, so using this function instead of write() can save cycles if the written data does not change often | ||
| + | |||
| + | |||
| + | <font color="orange" size="+1">'''示例'''</font> | ||
<pre style="color:dimgray"> | <pre style="color:dimgray"> | ||
#include <EEPROM.h> | #include <EEPROM.h> | ||
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void setup() | void setup() | ||
{ | { | ||
| − | + | for (int i = 0; i < 255; i++) { | |
| + | // this performs as EEPROM.write(i, i) | ||
| + | EEPROM.update(i, i); | ||
| + | } | ||
| + | for (int i = 0; i < 255; i++) { | ||
| + | // write value "12" to cell 3 only the first time | ||
| + | // will not write the cell the remaining 254 times | ||
| + | EEPROM.update(3, 12); | ||
| + | } | ||
} | } | ||
void loop() | void loop() | ||
{ | { | ||
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} | } | ||
2015年7月14日 (二) 10:29的版本
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update()
描述 Write a byte to the EEPROM. The value is written only if differs from the one already saved at the same address.
EEPROM.update(address, value)
address: the location to write to, starting from 0 (int) value: the value to write, from 0 to 255 (byte)
none
An EEPROM write takes 3.3 ms to complete. The EEPROM memory has a specified life of 100,000 write/erase cycles, so using this function instead of write() can save cycles if the written data does not change often
#include <EEPROM.h>
void setup()
{
for (int i = 0; i < 255; i++) {
// this performs as EEPROM.write(i, i)
EEPROM.update(i, i);
}
for (int i = 0; i < 255; i++) {
// write value "12" to cell 3 only the first time
// will not write the cell the remaining 254 times
EEPROM.update(3, 12);
}
}
void loop()
{
}
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