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#ifndef __LINUXMT_FDREG_H
#define __LINUXMT_FDREG_H

/* This file contains some defines for the floppy disk controller. Various
 * sources. Mostly "IBM Microcomputers: A Programmers Handbook" by Sanches
 * and Canton.
 */

/* Fd controller regs. S&C, about page 340 */
#define FD_STATUS       0x3f4   /* (MSR) Main Status Register */
#define FD_DATA         0x3f5   /* Data Register (FIFO) */
#define FD_DOR          0x3f2   /* Digital Output Register */
#define FD_DIR          0x3f7   /* Digital Input Register (read) (82077) */
#define FD_CCR          0x3f7   /* Configuration Control Register (write) (82077) */

/* Bits of main status register */
#define STATUS_BUSYMASK 0x0F    /* drive busy mask */
#define STATUS_BUSY     0x10    /* FDC busy */
#define STATUS_DMA      0x20    /* 0- DMA mode */
#define STATUS_DIR      0x40    /* 0- cpu->fdc */
#define STATUS_READY    0x80    /* Data reg ready */

/* Bits of FD_ST0 */
#define ST0_DS          0x03    /* drive select mask */
#define ST0_HA          0x04    /* Head (Address) */
#define ST0_NR          0x08    /* Not Ready */
#define ST0_ECE         0x10    /* Equipment chech error */
#define ST0_SE          0x20    /* Seek end */
#define ST0_INTR        0xC0    /* Interrupt code mask */

/* Bits of FD_ST1 */
#define ST1_MAM         0x01    /* Missing Address Mark */
#define ST1_WP          0x02    /* Write Protect */
#define ST1_ND          0x04    /* No Data - unreadable */
#define ST1_OR          0x10    /* OverRun */
#define ST1_CRC         0x20    /* CRC error in data or addr */
#define ST1_EOC         0x80    /* End Of Cylinder */

/* Bits of FD_ST2 */
#define ST2_MAM         0x01    /* Missing Addess Mark (again) */
#define ST2_BC          0x02    /* Bad Cylinder */
#define ST2_SNS         0x04    /* Scan Not Satisfied */
#define ST2_SEH         0x08    /* Scan Equal Hit */
#define ST2_WC          0x10    /* Wrong Cylinder */
#define ST2_CRC         0x20    /* CRC error in data field */
#define ST2_CM          0x40    /* Control Mark = deleted */

/* Bits of FD_ST3 */
#define ST3_HA          0x04    /* Head (Address) */
#define ST3_TZ          0x10    /* Track Zero signal (1=track 0) */
#define ST3_WP          0x40    /* Write Protect */

/* Values for FD_COMMAND */
#define FD_RECALIBRATE  0x07    /* move to track 0 */
#define FD_SEEK         0x0F    /* seek track */
#define FD_READ         0xE6    /* read with MT, MFM, SKip deleted */
#define FD_WRITE        0xC5    /* write with MT, MFM */
#define FD_SENSEI       0x08    /* Sense Interrupt Status */
#define FD_SPECIFY      0x03    /* specify HUT etc */
#define FD_FORMAT       0x4D    /* format one track */
#define FD_VERSION      0x10    /* get version code */
#define FD_CONFIGURE    0x13    /* configure FIFO operation (82072) */
#define FD_DUMPREGS     0x0E    /* dump the contents of the fdc regs (82072) */
#define FD_PERPENDICULAR 0x12   /* perpendicular r/w mode (82077) */

/* DMA commands */
#define DMA_READ        0x46
#define DMA_WRITE       0x4A

/* FDC chip/adapter types */
#define FDC_TYPE_8272A      1   /* IBM PC or PC/XT clone w/8272A (or NEC 765) */
#define FDC_TYPE_8272PC_AT  2   /* IBM PC/AT w/8272A has DIR/CCR on adaptor */
#define FDC_TYPE_82072      3   /* FDC accepts CONFIGURE, DUMPREGS */
#define FDC_TYPE_82077      4   /* FDC accepts PERPENDICULAR, LOCK */

#endif
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