Spectrum Controls 1746sc-CTR4 User Manual

Page 37

Chapter 4: Channel Configuration, Data, and Status

Input Registers -
Channel Data

The channel data consists of 4 words, the lower counter data value, the
upper counter data value, the rate data value and the channel status data.

Table 4.4 - Data Word Addresses

CTR8

CTR4

Scale/Limit Value

I:e.0 to I:e.3

0 Channel MSW, LSW, Rate Data, Status Reg

I:e.4 to I:e.7

1 Channel MSW, LSW, Rate Data, Status Reg

I:e.8 to I:e.11

2 Channel MSW, LSW, Rate Data, Status Reg

I:e.12 to I:e.15

3 Channel MSW, LSW, Rate Data, Status Reg

I:e.16 to I:e.19

(n/a)

4 Channel MSW, LSW, Rate Data, Status Reg

I:e.20 to I:e.23

(n/a)

5 Channel MSW, LSW, Rate Data, Status Reg

I:e.24 to I:e.27

(n/a)

6 Channel MSW, LSW, Rate Data, Status Reg

I:e.28 to I:e.31

(n/a)

7 Channel MSW, LSW, Rate Data, Status Reg

Figure 4.9 - Data Words

I:e.w

I:e.x

I:e.y

I:e.z

Rate Output

Counter MSW

Counter LSW

Status Output

Counter Output Register, High word:

This output data register contains the upper word of the counters
accumulator. This register is a 16 bit word in binary 2’s complement
format. When operating in the extended count mode, ±8M counts, the
high word is equal to the counter value/1,000 and the low word is the
remainder. For example, a count of 40,123 would result in a high word
equal to 40, and the low word equal to 123. The high word = 40 and the
low word = 123.

Figure 4.11 -Counter High Word

Counter Input High

This register is always zero when operating the the standard (32k) count
mode.