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**POKE(**//address//,//source//**)**

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| **POKE** | Writes data to a memory address. |
| //address// | A numeric constant, variable, or expression (evaluated to a LONG) which specifies a memory address. This parameter should always use the ADDRESS procedure, to ensure the correct protected mode address is used. |
| //source// | The label of a variable. |

The **POKE** statement writes the contents of the //source// variable to the memory address at //address//. POKE writes as many bytes as are in the //source// variable.

It is easily possible to create a General Protection Fault (GPF) if you POKE to an incorrect address, so great care should be taken when using POKE. There are usually Windows API functions that will do whatever you require of POKE and these should be used in preference to POKE.

**Example:**

**MAddress         LONG**

**Source1          BYTE**

**Source2          SHORT**

**Source3          REAL**

**KeyboardFlag     BYTE**

**   CODE**

**   ****POKE****(ADDRESS(MAddress),Source1)  !Write 1 byte to the memory location**

**   ****POKE****(ADDRESS(MAddress),Source2)  !Write 2 bytes to the memory location**

**   ****POKE****(ADDRESS(MAddress),Source3)  !Write 8 bytes to the memory location**

**   KeyboardFlag = BOR(KeyboardFlag,40h)   !turn on caps lock**

**   ****POKE****(ADDRESS(00400017h),KeyboardFlag)  !and put it back**

**See Also:**

[[peek  read memory address .htm|PEEK]]

[[address  return memory address .htm|ADDRESS]]