CompuScope SDK Manua.. - Egmont Instruments

gage_transfer_buffer
Syntax
C:
void GAGEAPI gage_transfer_buffer (int32 ta, int16 channel, void far *buffer, int32 nsamples);
Visual BASIC:
Sub gage_transfer_buffer (ByVal ta As Long, ByVal channel As Integer, buffer As Integer, ByVal
nsamples As Integer)
Remarks
gage_transfer_buffer is used to copy nsamples points from the specified channel to the supplied buffer
beginning from CompuScope on-board memory address ta. The channel can be either GAGE_CHAN_A
or GAGE_CHAN_B, and refers to the A/D converter memory bank. The relevant addresses can be
obtained by calling gage_calculate_addresses. The buffer must have been previously typecast to the
appropriate size. For 8 bit CompuScopes, the buffer should typecast for uInt8 values. For CompuScopes
with more than 8 bit resolution, the buffer should typecast for int16 values.
gage_transfer_buffer uses a CPU mediated PCI data transfer method. For the fastest PCI bus-mastering
data transfer, use gage_transfer_buffer_3.
For all CompuScope boards with two channels operating in single channel mode, both A/D converters are
used. The two converters are connected to the conditioned input from the Channel A BNC and are clocked
180 O out of phase. Data from each converter are then stored in their respective memory banks, as usual.
After capture, gage_transfer_buffer must then be used to download the data from both memory banks.
This is done by calling gage_transfer_buffer twice, once with channel equal to GAGE_CHAN_A , which
transfer the even points, and once with channel equal to GAGE_CHAN_B, which transfer the odd points..
The user must then interleave the two downloaded data sets in order to reconstruct the complete data
record.
Return Value
None.
See also
gage_transfer_buffer_3 and Appendix: Comparison of Various Data Transfer Routines.
Example
C:
gage_transfer_buffer (current_address, GAGE_CHAN_A, (uInt8 far *)(buffer), 512);
Visual Basic:
gage_transfer_buffer (ByVal ta As Long, ByVal channel As Integer, buffer As Integer, ByVal nsamples As
Integer)
CompuScope API Reference Manual 52