Clock generation

External clocking

 

 

ch0

ch1

ch2

ch3

ch4

ch5

ch6

ch7

Mode

EXRANGE_SINGLE

EXRANGE_BURST_S

EXRANGE_BURST_M

EXRANGE_BURST_L

EXRANGE_BURST_XL

x

 

 

 

 

 

 

 

Standard/FIFO

< 5 MHz

5 MHz - max

 

 

 

 

x

x

 

 

 

 

 

 

Standard/FIFO

< 2.5 MHz

2.5 MHz - 7.5 MHz

7.5 MHz - 17.5 MHz

17.5 MHz - 36 MHz

> 36 MHz

x

 

 

 

x

 

 

 

Standard

< 5 MHz

5 MHz - max

 

 

 

 

x

 

 

 

x

 

 

 

FIFO

< 2.5 MHz

2.5 MHz - 7.5 MHz

7.5 MHz - 17.5 MHz

17.5 MHz - 36 MHz

> 36 MHz

x

x

 

 

x

x

 

 

Standard

< 2.5 MHz

2.5 MHz - 7.5 MHz

7.5 MHz - 17.5 MHz

17.5 MHz - 36 MHz

> 36 MHz

x

x

 

 

x

x

 

 

FIFO

< 1.3 MHz

1.3 MHz - 3.8 MHz

3.8 MHz - 8.8 MHz

8.8

MHz - 18 MHz

> 18 MHz

x

x

x

x

 

 

 

 

Standard/FIFO

< 1.3 MHz

1.3 MHz - 3.8 MHz

3.8 MHz - 8.8 MHz

8.8

MHz - 18 MHz

> 18 MHz

x

x

x

x

x

x

x

x

Standard

< 1.3 MHz

1.3 MHz - 3.8 MHz

3.8 MHz - 8.8 MHz

8.8

MHz - 18 MHz

> 18 MHz

x

x

x

x

x

x

x

x

FIFO

< 0.7 MHz

0.7 MHz - 1.9 MHz

1.9 MHz - 4.4 MHz

4.4

MHz - 9 MHz

> 9 MHz

How to read this table? If you have activated all eight channels and are using the board in standard mode (not FIFO) and your external clock is known to be around 15 MHz you have to set the EXRANGE_BURST_L for the external range.

Example:

SpcSetParam (hDrv, SPC_CHENABLE,

CHANNEL0

CHANNEL1 CHANNEL2 CHANNEL3); //

activate

4 channels

SpcSetParam

(hDrv, SPC_EXTERNALCLOCK,

1);

 

//

activate

external clock

SpcSetParam

(hDrv, SPC_EXTERNRANGE, EXRANGE_BURST_M);

// set external range to Burst M

External clock with divider

The extra clock divider can be used to divide an external fed in clock by a fixed value. The external clock must be > 1 MS/s. This divided clock is used as a sample clock for the board.

Register

Value

Direction

Description

SPC_CLOCKDIV

20040

r/w

Extra clock divider for external samplerate. Allowed values are listed below

Available divider values

1

2

4

8

10

16

20

40

50

80

100

200

400

500

800

1000

2000

 

 

 

 

 

 

 

(c) Spectrum GmbH

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Image 61
Spectrum Brands MC.31XX manual External clock with divider, CHANNEL0 CHANNEL1 CHANNEL2 CHANNEL3, Fifo