7.Send three clock pulses to the internal high-speed bus by reading or writing (any value) to the pulse register (base + 0816) three times. This initializes the transfer stages.

8.Set the clock source to the digitizer data register.

A. In the traffic register (base + 0216), set the digitizer’s data register as the high-speed clock source by setting bits 3 - 2 as indicated:

bits 3 - 2 = 1 0

Setting the data register (base + 0C16) as the clock source transfers a reading from memory to the VME bus each time the data register is read.

Example Program

The following program demonstrates the procedures used to register program the digitizer. The program was developed using the configuration listed on page C-1. To adapt the program for use with an embedded controller, you will need to change the A24 base address accordingly, as well as make the modifications noted in the program listing.

This program accomplishes the following:

SCPI programming

configures the digitizer to take 20 readings on the 5V range using the CONFigure command, and then retrieves the readings using the READ? command.

Register programming

changes the measurement range to 1V

changes the trigger source to the reference oscillator period/N

sets the post-arm reading count to 20 readings

changes the sample rate to 10 kHz (100 μs)

re-initiates the digitizer to take the next 20 readings on the 1V range

retrieves the readings from memory by reading the data register. This places the readings on the VME(VXI data transfer) bus.

388 Register Programming

Appendix C

Page 388
Image 388
HP E1429A manual Example Program