1.1 --- a/src/io.h	Wed Jun 21 06:49:50 2017 +0300
     1.2 +++ b/src/io.h	Thu Jun 22 07:44:48 2017 +0300
     1.3 @@ -22,6 +22,9 @@
     1.4  #define IO_REG_LOCK		*((volatile uint8_t*)0xa14000)
     1.5  #define IO_REG_TMSS		*((volatile uint8_t*)0xa14101)
     1.6  
     1.7 +#define IO_REG_DATA(x)	*((volatile uint8_t*)0xa10003 + ((x) << 1))
     1.8 +#define IO_REG_CTRL(x)	*((volatile uint8_t*)0xa10009 + ((x) << 1))
     1.9 +
    1.10  
    1.11  enum {
    1.12  	IO_VER_VERSION_MASK = 0x0f,
    1.13 @@ -30,4 +33,32 @@
    1.14  	IO_VER_NONJP	= 0x80
    1.15  };
    1.16  
    1.17 +enum {
    1.18 +	IO_PAD_UP		= 1,
    1.19 +	IO_PAD_DOWN		= 2,
    1.20 +	IO_PAD_LEFT		= 4,
    1.21 +	IO_PAD_RIGHT	= 8,
    1.22 +	IO_PAD_B		= 16,
    1.23 +	IO_PAD_C		= 32,
    1.24 +	IO_PAD_A		= 64,
    1.25 +	IO_PAD_START	= 128
    1.26 +};
    1.27 +
    1.28 +static inline void io_setdir(int port, uint8_t dir)
    1.29 +{
    1.30 +	IO_REG_CTRL(port) = dir;
    1.31 +}
    1.32 +
    1.33 +static inline uint16_t io_readpad(int port)
    1.34 +{
    1.35 +	uint16_t bnstate;
    1.36 +
    1.37 +	io_setdir(port, 0x40);		/* pin 6 (multiplexer) output, 0-5 inputs */
    1.38 +	IO_REG_DATA(port) = 0x40;	/* select mode 1 */
    1.39 +	bnstate = IO_REG_DATA(port);
    1.40 +	IO_REG_DATA(port) = 0;		/* select mode 0 */
    1.41 +	bnstate |= (IO_REG_DATA(port) << 2) & (IO_PAD_A | IO_PAD_START);
    1.42 +	return bnstate;
    1.43 +}
    1.44 +
    1.45  #endif	/* MEGADRIVE_IO_H_ */