J
Jack// ani
- Jan 1, 1970
- 0
Hi all,
I'm making a 4x4 keypad for a DTMF dialer using on/off tactile
switch. Problem is Row and Column has internal pullup resistors, so
that to generate a tone you have to short the corresponding Row/Column
and pull it down to ground. Before this I have experienced with simple
keypad where no ground is required, I'm totally confused as how to
proceed. Please help me.
Thanks in advance
I'm making a 4x4 keypad for a DTMF dialer using on/off tactile
switch. Problem is Row and Column has internal pullup resistors, so
that to generate a tone you have to short the corresponding Row/Column
and pull it down to ground. Before this I have experienced with simple
keypad where no ground is required, I'm totally confused as how to
proceed. Please help me.
Thanks in advance