text: 
  #include "xf86RamDac.h"
  
  extern _X_EXPORT RamDacHelperRecPtr BTramdacProbe(ScrnInfoPtr pScrn, RamDacSupportedInfoRecPtr ramdacs);
  extern _X_EXPORT void BTramdacSave(ScrnInfoPtr pScrn, RamDacRecPtr RamDacRec, RamDacRegRecPtr RamDacRegRec);
  extern _X_EXPORT void BTramdacRestore(ScrnInfoPtr pScrn, RamDacRecPtr RamDacRec, RamDacRegRecPtr RamDacRegRec);
  extern _X_EXPORT void BTramdacSetBpp(ScrnInfoPtr pScrn, RamDacRegRecPtr RamDacRegRec);
  
  #define ATT20C504_RAMDAC 	(VENDOR_BT << 16) | 0x00
  #define ATT20C505_RAMDAC 	(VENDOR_BT << 16) | 0x01
  #define BT485_RAMDAC		(VENDOR_BT << 16) | 0x02
  
  /*
   * BT registers
   */
  
  #define BT_WRITE_ADDR		0x00
  #define BT_RAMDAC_DATA		0x01	
  #define BT_PIXEL_MASK		0x02
  #define BT_READ_ADDR		0x03
  #define BT_CURS_WR_ADDR		0x04
  #define BT_CURS_DATA		0x05
  #define BT_COMMAND_REG_0	0x06
  #define BT_CURS_RD_ADDR		0x07
  #define BT_COMMAND_REG_1	0x08
  #define BT_COMMAND_REG_2	0x09
  #define BT_STATUS_REG		0x0A
  #define BT_CURS_RAM_DATA	0x0B
  #define BT_CURS_X_LOW		0x0C
  #define BT_CURS_X_HIGH		0x0D
  #define BT_CURS_Y_LOW		0x0E
  #define BT_CURS_Y_HIGH		0x0F
  