46
•
Operation Theorem
♦
SC1 & SC0 - Select Counter ( Bit7 & Bit 6)
SC1
SC0
COUNTER
0
0
Select Counter 0
0
1
Select Counter 1
1
0
Select Counter 2
1
1
ILLEGAL
♦
RL1 & RL0 - Select Read/Load operation ( Bit 5 & Bit 4)
RL1
RL0
OPERATION
0
0
COUNTER LATCH FOR STABLE READ
0
1
READ/LOAD LSB ONLY
1
0
READ/LOAD MSB ONLY
1
1
READ/LOAD LSB FIRST, THEN MSB
♦
M2, M1 & M0 - Select Operating Mode ( Bit 3, Bit 2, & Bit 1)
M2
M1
M0
MODE
0
0
0
0
0
0
1
1
x
1
0
2
x
1
1
3
1
0
0
4
1
0
1
5
♦
BCD - Select Binary/BCD Counting ( Bit 0)
0
16-BITS BINARY COUNTER
1
BINARY CODED DECIMAL (BCD) COUNTER (4
DIGITAL)
Note
The count of the binary counter is from 0 up to
65,535 and the count of the BCD counter is from 0
up to 9,999
Mode Definitions
In 8254, six operating modes can be selected. they are:
•
Mode 0
: Interrupt on Terminal Count
•
Mode 1
: Programmable One-Shot.
•
Mode 2
: Rate Generator.
•
Mode 3
: Square Wave Rate Generator.
•
Mode 4
: Software Triggered Strobe.
Summary of Contents for ACL-8112 Series
Page 1: ...NuDAQ ACL 8112 Series Enhanced Multi Functions Data Acquisition Cards User s Guide ...
Page 4: ......
Page 40: ...32 Registers Format 1 1 1 1 1 000 Unipolar N A Table 4 2 1 Function of the Gain Control Bits ...
Page 44: ...36 Registers Format Base 14 DO15 DO14 DO13 DO12 DO11 DO10 DO9 DO8 ...
Page 46: ...38 Registers Format Base 2 Counter 2 Register R W Base 3 8254 CONTROL BYTE ...
Page 71: ...C Language Library 63 ...
Page 81: ...C Language Library 73 Example See Demo Program AD_Demo4 C ...
Page 85: ...C Language Library 77 ERR_AD_INTNotSet Example See demo program AD_Demo2 C ...