MOGlabs ARF021, Руководство пользователя

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Chapter 7. Digital I/O
H[IGH]
Count while input is HIGH , enables counter
L[OW]
Count while input is LOW , enables counter
R[ISING]
Count rising edges, enables counter
F[ALLING]
Count falling edges, enables counter
B[OTH]
Count both rising and falling edges, enables counter
The following NSB -mode example sets up a rising edge counter on
HSB3 and counts for approximately 100 ms.
1
EXTIO,MODE,2,HSB,READ
EXTIO,COUNTER,2,HS3,RISING
EXTIO,COUNTER,2,HS3,RESET
SLEEP,100
# wait approximately 100ms
EXTIO,COUNTER,2,HS3,READ
# returns counts recorded
7.8 Examples
The following examples demonstrate how to configure and use the
external I/O pins. Note that pins must be set to MANUAL using the
EXTIO,CTRL
command to be used for READ and WRITE .
These commands may be useful in executing scripts or diagnosing
experiments. For any application where timing is important, table
mode should be used.
EXTIO,CTRL,1,HSB,MAN
Set HSB1 to MANUAL mode, for use with READ and WRITE
EXTIO,WRITE,1,DOUT,1
Sets the CH1-DOut pin ( DB15 ) to HIGH
EXTIO,READ,2,OFF
Reads the current state of the
CH2-OFF
pin (
DB15
)
EXTIO,MODE,1,HSB,WRITE
Set the entire first high-speed bank into write mode
1
Advanced table mode should be used for more accurate measurement (
§
9.4).