mirror of
https://github.com/ekeeke/Genesis-Plus-GX.git
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96 lines
2.3 KiB
C
96 lines
2.3 KiB
C
/***************************************************************************************
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* Genesis Plus
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* Sega Paddle Control support
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*
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* Copyright Eke-Eke (2007-2011)
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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*
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****************************************************************************************/
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#include "shared.h"
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static struct
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{
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uint8 State;
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} paddle[2];
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void paddle_reset(int index)
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{
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input.analog[index << 2][0] = 128;
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paddle[index].State = 0x40;
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}
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static inline unsigned char paddle_read(int port)
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{
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/* FIRE button status (active low) */
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unsigned char temp = ~(input.pad[port] & 0x10);
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/* Pad index */
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int index = port >> 2;
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/* Clear low bits */
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temp &= 0x70;
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/* Japanese model: automatic flip-flop */
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if (region_code < REGION_USA)
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{
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paddle[index].State ^= 0x40;
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}
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if (paddle[index].State & 0x40)
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{
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/* return higher bits */
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temp |= (input.analog[port][0] >> 4) & 0x0F;
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}
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else
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{
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/* return lower bits */
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temp |= input.analog[port][0] & 0x0F;
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/* set TR low */
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temp &= ~0x20;
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}
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return temp;
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}
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static inline void paddle_write(int index, unsigned char data, unsigned char mask)
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{
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/* update bits set as output only */
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paddle[index].State = (paddle[index].State & ~mask) | (data & mask);
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}
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unsigned char paddle_1_read(void)
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{
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return paddle_read(0);
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}
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unsigned char paddle_2_read(void)
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{
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return paddle_read(4);
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}
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void paddle_1_write(unsigned char data, unsigned char mask)
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{
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paddle_write(0, data, mask);
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}
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void paddle_2_write(unsigned char data, unsigned char mask)
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{
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paddle_write(1, data, mask);
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}
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