UINT8 mboard_state::read_board()
{
UINT8 i_18, i_AH;
UINT8 data;
data = 0xff;
/*
Example board scan:
Starting postion and pawn on E2 is lifted
mask: 7f 0111 1111 Line 8
data: 0 0000 0000 all fields occupied
mask: bf 1011 1111 Line 7
data: 0 0000 0000 all fields occupied
mask: df 1101 1111 Line 6
data: ff 1111 1111 all fields empty
mask: ef 1110 1111 Line 5
data: ff 1111 1111 all fields empty
mask: f7 1111 0111 Line 4
data: ff 1111 1111 all fields empty
mask: fb 1111 1011 Line 3
data: ff 1111 1111 all fields empty
mask: fd 1111 1101 Line 2
data: 10 0001 0000 E2 is empty rest is occupied
mask: fe 1111 1110 Line 1
data: 0 0000 0000 all fields occupied
*/
/* looking for cleared bit in mask Line18_REED => current line */
if (data && Line18_REED)
{
i_18 = get_first_cleared_bit(Line18_REED);
if (i_18 == NOT_VALID)
printf("No cleared bit in mask Line18_REED!\n");
else
{
/* looking for a piece in this line and clear bit in data if found */
for (i_AH = 0; i_AH < 8; i_AH = i_AH + 1)
if (IsPiece(64 - (i_18 * 8 + 8 - i_AH)))
data &= ~(1 << i_AH); // clear bit
read_board_flag = TRUE;
}
}
return data;
}
static READ8_HANDLER( supercon_port4_r )
{
supercon_state *state = space->machine().driver_data<supercon_state>();
int i_18, i_AH;
UINT8 key_data = 0x00;;
static const char *const board_lines[8] =
{ "BOARD_1", "BOARD_2", "BOARD_3", "BOARD_4", "BOARD_5", "BOARD_6", "BOARD_7", "BOARD_8" };
LOG(("Read from %04x \n",0x1F00));
/* Board buttons */
i_18=get_first_bit(state->m_data_1E00);
if (i_18==NOT_VALID)
return 0xff;
/* if a button was pressed wait til timer -timer_mouse_click- is fired */
if (state->m_selecting)
return state->m_save_key_data;
else
{
set_pieces(state);
output_set_value("MOVING",state->m_moving_piece);
}
key_data=input_port_read(space->machine(), board_lines[i_18]);
if (key_data != 0xff)
{
LOG(("%s key_data: %02x \n",board_lines[i_18],key_data));
/* Only if valid data and mouse button is pressed */
if (key_data && input_port_read(space->machine(), "BUTTON_L"))
{
/* Set or remove pieces */
i_AH=7-get_first_cleared_bit(key_data);
LOG(("Press -> AH: %d 18: %d Piece: %d\n",i_AH,i_18,state->m_board[i_18*8 + i_AH]););
