SENA HD1200 - Manual (Page 44)

Starter Kit and User Manual for the HelloDevice 1200
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; Do something required to control user device by using the data read
2) A/D Converter Test
Refer to the included specifications of both the HelloDevice external interface and Demo Board ADC connector
for hardware implementation. Next, refer to the A/D converter Data Sheet attached to this manual for National
Semiconductor’s ADC0804.. 8 data lines and 4 control lines are required for an A/D converter interface.
5V DC signal is connected to input line of A/D converter. By changing the value of 10K variable resistor on
Demo Board, the input value of A/D converter is changed. You can implement a simple program to read output
of A/D converter and to write this numeric to specified location of Dual-Port RAM. Eventually, you can test the
change of the A/D converter output, if you poll the HelloDevice Dual-Port RAM by using socket interface
program.
3) I/O Control Test
When you select the switch of Demo Board, a signal of 5V TTL level falls from high to low on the input line
(Low Active). Your device may read the status of input line and write the result to Dual-Port RAM. Also, your
device may read data from the specified location of Dual-Port RAM, and then turn on/off the LED of Demo
Board by setting output line as 5V HIGH level. If the output is High, LED turns on (High Active).