26
6.4 Counter Cards - Natural Binary Output
Table 6E is based upon a counter card with [÷1] divider (factory set). A single card is capable of 18 bits
natural binary output maximum.
For the 27-28 MHz crystal, the resulting resolution and recirculations versus stroke are as follows:
Resolution Circulations Stroke Length
0.000125 32 Up to 32 inches
0.00025 16 Up to 65 inches
0.0005 8 Up to 131 inches
0.001 4 Up to 262 inches
0.002 2 Up to 300 inches
0.004 1 Up to 300 inches
Table 6E Counter Card Output (÷1)
Pin No. Bit Weight Decimal Value Bit Maximum Counts vs.
Number of Bits
10 LSB
1
2
0
1 = 1 bit
9 2
1
3 = 2 bits
8 2
2
7 = 3 bits
7 2
3
15 = 4 bits
14 2
4
31 = 5 bits
13 2
5
63 = 6 bits
12 2
6
127 = 7 bits
11 2
7
255 = 8 bits
18 2
8
511 = 9 bits
17 2
9
1023 = 10 bits
16 2
10
2047 = 11 bits
15 2
11
4095 = 12 bits
20 2
12
8191 = 13 bits
21 2
13
16,383 = 14 bits
22 2
14
32,767 = 15 bits
19 2
15
65,535 = 16 bits
23 2
16
131,071 = 17 bits
25 MSB
2
2
17
262,143 = 18 bits
NOTES:
1. LSB = Least Significant Bit
2. MSB = Most Significant Bit. MSB is determined by dividing the stroke length by the resolution and comparing to the maximum count.
For Example: 25 in./0.001 = 25,000; this requires a maximum count of 32,767, thus yielding an MSB at Pin 22.