Martianoids: Routine at A6AE

A6AE: Use Energy

Used by the routines at FireWeaponB and GetRobotSpeed.

Takes an amount of energy out of the battery. If there is not enough then the battery is empty and the robot is destroyed, along with all of the enemies. The energy is free once every sector has been either activated or destroyed.

Input
DE	Energy to use

Output
F	The carry flag is set if there was not enough energy

UseEnergy

A6AE

LD A,($9658)

Fetch the number of sectors that have been activated.

A6B1

LD L,A

Keep the number of activated sectors.

A6B2

LD A,($9659)

Fetch the number of sectors that have been destroyed.

A6B5

ADD A,L

Add the number that have been activated...

A6B6

LD ($965A),A

...and store the number of sectors that have been dealt with.

A6B9

CP $09

Jump if some sectors have not been dealt with.

A6BB

JR NZ,UseEnergy_Take

A6BD

AND A

Otherwise clear the carry flag and return, as the energy is free.

A6BE

RET

UseEnergy_Take

A6BF

LD HL,($963A)

Fetch the energy of the battery.

See Infinite Energy.

A6C2

AND A

Subtract the energy that is to be used.

A6C3

SBC HL,DE

A6C5

JR C,UseEnergy_Empty

Jump if there is not enough energy.

A6C7

LD ($963A),HL

Otherwise store the new energy...

A6CA

RET

...and return.

UseEnergy_Empty

A6CB

LD HL,$0000

The battery is empty.

A6CE

LD ($963A),HL

Store that.

A6D1

PUSH AF

Save the carry flag.

A6D2

LD A,$38

Turn the robot into smoke...

A6D4

LD ($9690),A

...by setting its type to 38.

A6D7

XOR A

Clear the controls...

A6D8

LD ($9625),A

...so that nothing is fired.

A6DB

CALL ExplodeEnemies

Turn all of the enemies into smoke using ExplodeEnemies.

A6DE

POP AF

Restore the carry flag...

A6DF

RET

...and return.