Chapter 3 Theory of Operation
AT-MIO-16X User Manual 3-24
©
National Instruments Corporation

In the pulsed waveform application, Counter 1 of the Am9513A is

programmed to count the number of retransmit signals, before

terminating the sequence. At this point, Counter 2 serves as an interval

timer and then restarting the sequence. This process proceeds ad

infinitum until the timer trigger is removed or disabled, or the

CYCLICSTOP bit is set.

Digital I/O Circuitry

The AT-MIO-16X has eight digital I/O lines. These eight digital I/O

lines are divided into two ports of four lines each and are located at pins

ADIO<3..0> and BDIO<3..0> on the I/O connec tor. Figure 3-16 shows

a block diagram of the digital I/O circuitry.

Figure 3-16. Digital I/O Circuitry Block Diagram

I/O Connector
A
Digital
Input
Register
B
DOUT0
Digital
Output
Register
DOUT1
Digital
Output
Register
EXT STROBE WR*
EXTSTROBE*
/
4
/
4
/
4
/
4
DO REG WR
DOUT0 ENABLE
/
4
DATA <3..0>
DATA <7..4>
/
4
DOUT1 ENABLE
DIREG RD
DATA <7..0>
/
8
BDIO <3..0>
ADIO <3..0>
PC I/O Channel