Using two port pins of 8051, P1.0 and P1.1, a hardware interface for a 12 V DC motor through L293D is pre-
sented in Fig. 21.10. To use another DC motor of some other voltage, say 9 V, the Vs input (pin 8) of L293D
is to be changed to 9 V DC. Note the presence of a pair of pull-up resistors of 10K each at the Port 1 output.
Half of the L293D was disabled by grounding its ENABLE 2 input. Furthermore, its unused input pins 10
and 15 are also connected with system ground. e output through two port pins must be complementary to
run the motor. at is, if P1.0 is high, then P1.1 must be low and vice versa. A software routine (DCDIR) to ...
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month, and much more.