Description
The VMIVME-3122 board contains the following principal hardware functions, as shown in Figure 1-1 on page 21: • Analog input multiplexing and digitizing • VMEbus interface • Scan timing and control • Data and gain buffers • Interval timer and channel counter (Intel 8254) • Bus interrupter • Power converter Input Buffers, Analog Multiplexers, a Programmable Amplifier and a 16-bit A/D Converter digitize the analog input channels. The digitized values are stored in a dual-ported data buffer for access from the VMEbus. Optional low pass input filters minimize the effects of system noise and eliminate high frequency signal components which would otherwise cause accuracy problems. Input Buffers eliminate the error associated with varying source resistance. The scan rate is selectable from 381 Hz to 100 kHz for high-performance mode, and 381 Hz to 50 kHz for standard performance mode according to the scan rate equations in the Rate Control Register (RCR) on page 64. Operating modes are described in detail in Operating Modes on page 75. Regulated ±15 VDC power for the analog networks is obtained from the 5 VDC bus through a DC-to-DC Converter.
VMIVME-3122-210-VMIVME3122
