Trashman: Routine at A675

A675: Game Selection Menu

Used by the routine at GameEntryPoint.

Prints "Please select method of control".

GameMenu A675 LD HL,$AB8B HL=Messaging_SelectControl.

A678 LD DE,$4820 DE=4820 (screen buffer location).

A67B CALL PrintString Call PrintString.

Prints "1 : Keyboard ( cursor keys )".

A67E LD HL,$ABAB HL=Messaging_SelectKeyboard.

A681 LD DE,$4861 DE=4861 (screen buffer location).

A684 CALL PrintString Call PrintString.

Prints "2 : Kempston joystick".

A687 LD HL,$ABC8 HL=Messaging_SelectKempston.

A68A LD DE,$4881 DE=4881 (screen buffer location).

A68D CALL PrintString Call PrintString.

Prints "3 : Interface 2".

A690 LD HL,$ABDE HL=Messaging_SelectInterface2.

A693 LD DE,$48A1 DE=48A1 (screen buffer location).

A696 CALL PrintString Call PrintString.

Prints "4 : Cursor key type joysticks".

A699 LD HL,$ABEE HL=Messaging_SelectCursor.

A69C LD DE,$48C1 DE=48C1 (screen buffer location).

A69F CALL PrintString Call PrintString.

Handle retrieving the players input.

A6A2

LD BC,$F7FE

Read from the keyboard;

Port Number	Bit
Port Number	0	1	2	3	4
F7	1	2	3	4	5

GameMenu_Loop A6A5 IN A,(C)

A6A7 BIT 0,A If "1" is pressed, set HL to Handler_Controls_Keyboard and jump to GameMenu_WriteControl.

A6A9 LD HL,$B6BF

A6AC JR Z,GameMenu_WriteControl

A6AE BIT 3,A If "4" is pressed jump to GameMenu_WriteControl.

A6B0 JR Z,GameMenu_WriteControl

A6B2 LD HL,$B6E5 If "2" is pressed, set HL to Handler_Controls_Kempston and jump to GameMenu_WriteControl.

A6B5 BIT 1,A

A6B7 JR Z,GameMenu_WriteControl

A6B9 LD HL,$B703 If "3" is not pressed, set HL to Handler_Controls_Interface2 and jump to GameMenu_Loop.

A6BC BIT 2,A

A6BE JR NZ,GameMenu_Loop

The controller routine is written as the target address for a CALL operation at Handler_Controls.

GameMenu_WriteControl A6C0 LD ($B6BC),HL Write the appropriate controller location from HL into the CALL target at *B6BC.

A6C3 CALL PressAnyKey_0 Call PressAnyKey_0.

A6C6 RET Return.