Spectrum Controls 140 EHC 204 00sc - Manual (Page 35)

Quantum Series 140 EHC 204 00sc 140 EHC 208 00sc
36
R Rate Factor:
The R scale factor can be used for scaling of the output frequency. The output frequency is
divided by the R scale value. Typically a factor of two will be used. The result is the rate data value
being 1/2 of the actual value. R factors must be positive numbers.
Rate Output Value = Actual Rate Value / R Factor
Layout for 4X+2 through 4X+9 Registers
Registers 4X+2 through 4X+9 registers contain control word information for the each channel. The information
includes runtime configuration and control options. The next table shows the bit settings for these control word
registers.
Function 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Disable Start ` 0
Stop 1
Preset Off 0
On 1
Reset Counter No Reset 0
Reset 1
Gate Enable Disable 0
Enable 1
Count direction Up 0
Down 1
Reset flags Normal 0
Reset 1
Stop on zero Off 0
On 1
Stop on limit Off 0
On 1
Rate Mode Average 0
Instantaneous 1
Roll Over To Zero 0
Preset 1
Roll Under to Max Count 0
Preset 1
Unused X X X X X
Apply M Factor Apply 0
Do Not Apply 1
Counter Enable, Bit 16
Set bit 16 to 1 to enable the counter to continue to count up or down from its present value. Use
a setting of 0 to stop the counter. Enabling the counter using bit 16 does not override the external
counter enable input. Both bit 16 of the control word register and the input must be enabled for the
counter to continue counting. If either is disabled, the counter will hold its last value and stop
counting.