SECTION C $-$ AVR PERIPHERAL SYSTEMS

Please answer this section in a separate book that is titled "Section C$"$ on the front cover. This section is worth $40$ marks. If a value for a particular parameter, e$.$g$.$ prescaler, is not given, choose yours and indicate it$.$ In all cases show your working.

QUESTION C$1$

$[20]$

For a clock frequency of $8MHz,$ you are required to write a program to simultaneously sound a buzzer and drive a motor continuously. The buzzer, connected to PORTB$\mathrm{.}1,$ should be driven by a $1KHz$ square wave generated by TMR$1$ overflow interrupt. The motor, connected to OCO pin, should be driven by a $2KHz$ square wave generated by TMRO in the CTC mode toggling the OCO pin. Use a prescaler setting of $64$ for TMRO and no prescaler for Timer $1.$

a$)$ For driving the motor with TMRO in CTC mode and toggling the OCO pin. $[10]$

i$.)$ Determine the time it will take to toggle the OCO pin.

ii$.)$ Determine the value to be loaded in the OCRO and write assembler instructions to configure the register.

iii.$)$ Determine the value to be loaded in the TCCRO and write assembler instructions to configure the register.

$[4]$

b$)$ For driving the buzzer with TMR$1$ overflow interrupt.

$[10]$

i$.)$ Determine the time it takes for the interrupt to occur.

$[1]$

ii$.)$ Determine the value to be loaded in the TCNT$1$H and TCNT$1$L$.$

$[3]$

iii.$)$ Determine the value to be loaded in the TCCR$1$A and TCCR$1$B$.$

$[4]$

iv$.)$ Determine the value to be loaded in the TIMSK.

$[2]$

$4$