====== HRead( ) ======

''variable = HRead (address, byteLength)''
| //variable// | Variable to store results   |
| //address// | Heap address    |
| //byteLength // |Number of bytes to read, constant or variable (1 to 4)   |

This function supports only CB405 and CB405RT modules.

Read the designated number of bytes set by //length// from heap address, //address//, and store into **variable**.

<code xbasic>
Dim A As Integer
Dim B As Integer
A = 100
HWrite 0,A,2          ' Write integer A to address 0.
B = HRead(0,2)        ' Read from address 0 and store in B.
</code>

===== About Heap Memory =====

Heap memory access is a special feature only available on the CB405/CB405RT module. 
The user may use 55KB of heap memory from address 0 through
56831 (&H0000 through &HDDFF). The heap can be used to store large
data for graphics, temperature tables, etc. With a backup battery, the heap
can be used for data logging and other persistent uses.

{{ :cubloc:hread:heapmemory.png?nolink |}}

EERead and EEWrite have same syntax as HRead and HWrite.

^Function ^Memory Type ^Feature^
|EERead,EEWrite|EEPROM |Retains data during power cycles without a battery. The EEWrite command takes about 5ms. 4KB of available memory |
|HRead,HWrite|SRAM |Retains data during power cycles with a backup battery. Without a backup battery, data is lost. HWrite command takes about 20 microseconds to execute, much faster compared to EEWrite. 55KB of available memory |


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