Instrument Control Toolbox

MemoryBase

Indicate the base address of the A24 or A32 space

Description

MemoryBase indicates the base address of the A24 or A32 space. The value is returned as a string representing a hexadecimal value.

All VXI instruments have an A16 address space that is 16 bits wide. There are also 24- and 32-bit wide address spaces known as A24 and A32. Some instruments require the additional memory associated with the A24 or A32 address space when the 64 bytes of A16 space are insufficient for performing necessary functions. A bit in the A16 address space is set allowing the instrument to recognize commands to its A24 or A32 space.

An instrument cannot use both the A24 and A32 address space. The address space is given by the MemorySpace property. If MemorySpace is A16, then MemoryBase is 0H.

Characteristics

Usage	VISA-VXI, VISA-GPIB-VXI
Read only	Always
Data type	String

Values

The default value is 0H.

Example

Create the VISA-VXI object vv associated with a VXI chassis with index 0, and an Agilent E1432A digitizer with logical address 130.

• vv = visa('agilent','VXI0::130::INSTR');
  fopen(vv)
  

The MemorySpace property indicates that the A24 memory space is supported.

• vv.MemorySpace
  ans =
  A16/A24
  

The base address of the A24 space is

• vv.MemoryBase
  ans =
  '200000H'
  

See Also

Properties

MemorySpace

MappedMemorySize

MemoryIncrement