identify.h

Go to the documentation of this file.

 
#pragma once
 
#include <stdbool.h>
#include <stdint.h>
 
/*
 * Joybus device type flags.
 *
 * The first two bytes of the identify response contain the device type flags.
 *
 * The following flags map to the little-endian representation of the first two
 * bytes of the identify response. We're using a little-endian representation,
 * since modern microcontrollers are pretty much all little-endian by default.
 * This helps us avoid byte swapping when parsing the identify response, we can
 * cast the bytes to a joybus_id struct and use these masks as-is.
 */
 
// Non-GameCube device types
#define JOYBUS_TYPE_N64_MASK                  0x1f07  
#define JOYBUS_TYPE_N64_ABSOLUTE              0x0001  
#define JOYBUS_TYPE_N64_RELATIVE              0x0002  
#define JOYBUS_TYPE_N64_JOYPORT               0x0004  
#define JOYBUS_TYPE_N64_VRU                   0x0100  
#define JOYBUS_TYPE_N64_KEYBOARD              0x0200  
#define JOYBUS_TYPE_GBA_CABLE                 0x0400  
#define JOYBUS_TYPE_N64_RTC                   0x1000  
#define JOYBUS_TYPE_N64_EEPROM_16K            0x4000  
#define JOYBUS_TYPE_N64_EEPROM                0x8000  
 
// GameCube device types
#define JOYBUS_TYPE_GCN_MASK                  0x0018  
#define JOYBUS_TYPE_GCN_STANDARD              0x0001  
#define JOYBUS_TYPE_GCN_WIRELESS_STATE        0x0002  
#define JOYBUS_TYPE_GCN_DEVICE                0x0008  
#define JOYBUS_TYPE_GCN_NO_MOTOR              0x0020  
#define JOYBUS_TYPE_GCN_WIRELESS_RECEIVED     0x0040  
#define JOYBUS_TYPE_GCN_WIRELESS              0x0080  
#define JOYBUS_TYPE_GCN_WIRELESS_ID_FIXED     0x1000  
#define JOYBUS_TYPE_GCN_KEYBOARD              0x2000  
#define JOYBUS_TYPE_GCN_WIRELESS_ORIGIN       0x2000  
#define JOYBUS_TYPE_GCN_WIRELESS_ID_MASK      0xC000  
 
/*
 * Joybus device status flags.
 *
 * The last byte of the identify response contains the device "status" flags.
 */
 
// Status flags for N64 controllers with a Joyport
#define JOYBUS_STATUS_N64_PAK_PRESENT         0x01    
#define JOYBUS_STATUS_N64_PAK_PULLED          0x02    
#define JOYBUS_STATUS_N64_ADDR_CHECKSUM_ERROR 0x04    
 
// Status flags for N64 Voice Recognition Unit
#define JOYBUS_STATUS_N64_VRU_INITIALIZED     0x01    
 
// Status flags for non-wireless GameCube controllers
#define JOYBUS_STATUS_GCN_ANALOG_MODE_MASK    0x07    
#define JOYBUS_STATUS_GCN_MOTOR_STATE_MASK    0x18    
#define JOYBUS_STATUS_GCN_NEED_ORIGIN         0x20    
#define JOYBUS_STATUS_GCN_ERROR_LATCHED       0x40    
#define JOYBUS_STATUS_GCN_ERROR               0x80    
#define JOYBUS_STATUS_GCN_MOTOR_STATE_SHIFT   3
#define JOYBUS_STATUS_GCN_ANALOG_MODE_SHIFT   0
 
// Status flags for wireless GameCube controllers
#define JOYBUS_STATUS_GCN_WIRELESS_ID_MASK    0xFF    
 
/*
 * Complete type flags a device reports at power on.
 *
 * Most controllers keep the type field constant, but since wireless GameCube
 * controllers use the status field to hold the wireless ID, they add flags
 * to the type field at runtime instead to indicate their state.
 */

#define JOYBUS_DEVICE_N64_CONTROLLER  (JOYBUS_TYPE_N64_ABSOLUTE | JOYBUS_TYPE_N64_JOYPORT)

#define JOYBUS_DEVICE_N64_MOUSE       (JOYBUS_TYPE_N64_RELATIVE)

#define JOYBUS_DEVICE_GCN_CONTROLLER  (JOYBUS_TYPE_GCN_DEVICE | JOYBUS_TYPE_GCN_STANDARD)

#define JOYBUS_DEVICE_GCN_WAVEBIRD    (JOYBUS_TYPE_GCN_DEVICE | JOYBUS_TYPE_GCN_WIRELESS | JOYBUS_TYPE_GCN_NO_MOTOR)

struct joybus_id {
  uint16_t type;

  uint8_t status;
} __attribute__((packed));

static inline void joybus_id_clear_type_flags(struct joybus_id *id, uint16_t flags)
{
  id->type &= ~flags;
}

static inline void joybus_id_set_type_flags(struct joybus_id *id, uint16_t flags)
{
  id->type |= flags;
}

static inline void joybus_id_clear_status_flags(struct joybus_id *id, uint8_t flags)
{
  id->status &= ~flags;
}

static inline void joybus_id_set_status_flags(struct joybus_id *id, uint8_t flags)
{
  id->status |= flags;
}

static inline uint16_t joybus_id_get_wireless_id(const struct joybus_id *id)
{
  return (uint16_t)((id->type & 0xC000) >> 6 | id->status);
}

static inline void joybus_id_set_wireless_id(struct joybus_id *id, uint16_t wireless_id)
{
  id->type   = (id->type & ~0xC000) | ((uint16_t)((wireless_id >> 2) & 0xC0) << 8);
  id->status = wireless_id & 0xFF;
}

static inline bool joybus_id_n64_pak_changed(const struct joybus_id *id)
{
  return (id->status & JOYBUS_STATUS_N64_PAK_PRESENT) && (id->status & JOYBUS_STATUS_N64_PAK_PULLED);
}