spec

Software for Diffraction

2.4.8.9. - VME Hardware Functions



The type of data access and/or VME address modifier for the following functions can be selected with the optional argument dmode as follows (if more than one option is needed, make a comma-separated list in the single string argument):


"D8"
byte access

"D16"
short-word access

"D32"
long-word access, but only available with vme_get32() and vme_put32().

"DPRT"
use the address modifier appropriate for dual-port memory access, on adapters that support it.

"amod=0xXX"
specify the hexadecimal value for the address modifier.


The default mode for the A16 access functions vme_get() and vme_put() is D8. The default mode for the A32 access functions vme_get32() and vme_put32() is D32. Not all VME adapters supported by spec support A32 access. There are currently no functions for A24 access.


vme_get(addr [, dmode ])
Returns the data at addr in the 64K A16 address space.

vme_put(addr, data [, dmode ])
Writes data to addr in the 64K A16 address space.

vme_get32(addr [, dmode ])
Returns the data at addr in the A32 address space.

vme_put32(addr, data [, dmode ])
Writes data to addr in the A32 address space.

vme_move(from, to [, cnt [, dmode ]])
Copies data between a spec data array and VME A32 address space. One of the from and to arguments must be the name of a spec data array while the other must be a VME address. If the optional argument cnt is present, it designates how many data items (not bytes) to copy. If missing or zero, the number of elements in the array is copied.