Measurement-computing USB-4302 Manuel d'utilisateur télécharger pdf (Page 16)

USB-4302 User's Guide Functional Details

Oscillator output (OSC OUT)

The oscillator output connector (pin 30) outputs a configurable clock frequency. You can select the source of

the oscillator and also select dividers for the oscillator programmatically to set the output rate.

Ground (GND)

The ground (GND) connector (pin 11) provides a common ground for the digital and counter I/O connections.

Oscillator output

You can set the oscillator input programmatically to one of five internal frequency sources or one of 10 external

input pins. The oscillator output can be divided by any number from 1 to 16 before being output to the OSC

OUT pin.

Internal sources

The base frequency for the internal frequency sources can be set through InstaCal to one of four different

frequencies — 1.0000 MHz, 1.6667 MHz, 3.3333 MHz, or 5.0000 MHz. This base frequency is used to

generate the five internal frequency sources — FREQ1 through FREQ5.

FREQ1 is the same as the base frequency, and each successive internal frequency following FREQ1 divides the

base frequency by another multiple of 10. For example, FREQ2 is the base frequency divided by 10, FREQ3 is

the base frequency divided by 100, and so on. This is illustrated in the following table.

Internal frequency values for different base frequencies

1.0000 MHz

1.6667 MHz

3.3333 MHz

5.0000 MHz

FREQ1

1.0000 MHz

1.6667 MHz

3.3333 MHz

5.0000 MHz

FREQ2

100.00 kHz

166.67 kHz

333.33 kHz

500.00 kHz

FREQ3

10.000 kHz

16.667 kHz

33.333 kHz

50.000 kHz

FREQ4

1.0000 kHz

1.6667 kHz

3.3333 kHz

5.0000 kHz

FREQ5

100.00 Hz

166.67 Hz

333.33 Hz

500.00 Hz

External sources

In addition to the five internal sources, the frequency source for the oscillator can be an input signal connected

to any of the five counter input pins (CTR1IN – CTR5IN) or any of the five gate pins (CTR1GATE –

CTR5GATE). The input signal can have a maximum frequency of 20 MHz on the counter input pins, and a

maximum frequency of 7 MHz on the gate pins.

The table below applies to all internal and external sources.

Oscillator sources

Source

Description

CTRINPUT1

Counter 1 input pin

CTRINPUT2

Counter 2 input pin

CTRINPUT3

Counter 3 input pin

CTRINPUT4

Counter 4 input pin

CTRINPUT5

Counter 5 input pin

GATE1

Counter 1 gate pin

GATE2

Counter 2 gate pin

1 2 ... 11 12 13 14 15 16 17 18 19 20 21 ... 27 28

Commentaires sur ces manuels

Pas de commentaire

Measurement-computing USB-4302 Manuel d'utilisateur Page 16

Commentaires sur ces manuels

Produits connexes et manuels pour Matériel Measurement-computing USB-4302