DSP56K(4)                                           Linux Programmer's Manual                                          DSP56K(4)



NAME
       dsp56k - DSP56001 interface device

SYNOPSIS
       #include <asm/dsp56k.h>

       ssize_t read(int fd, void *data, size_t length);
       ssize_t write(int fd, void *data, size_t length);

       int ioctl(int fd, DSP56K_UPLOAD, struct dsp56k_upload *program);
       int ioctl(int fd, DSP56K_SET_TX_WSIZE, int wsize);
       int ioctl(int fd, DSP56K_SET_RX_WSIZE, int wsize);
       int ioctl(int fd, DSP56K_HOST_FLAGS, struct dsp56k_host_flags *flags);
       int ioctl(int fd, DSP56K_HOST_CMD, int cmd);

CONFIGURATION
       The dsp56k device is a character device with major number 55 and minor number 0.

DESCRIPTION
       The Motorola DSP56001 is a fully programmable 24-bit digital signal processor found in Atari Falcon030-compatible comput-
       ers.  The dsp56k special file is used to control the DSP56001, and to send and receive data using the bidirectional hand-
       shaked host port.

       To  send  a  data stream to the signal processor, use write(2) to the device, and read(2) to receive processed data.  The
       data can be sent or received in 8, 16, 24, or 32-bit quantities on the host side, but will always be seen as 24-bit quan-
       tities in the DSP56001.

       The following ioctl(2) calls are used to control the dsp56k device:

       DSP56K_UPLOAD
              resets  the  DSP56001  and  uploads  a  program.   The  third  ioctl(2)  argument  must  be  a pointer to a struct
              dsp56k_binary with members bin pointing to a DSP56001 binary program, and len set to the length  of  the  program,
              counted in 24-bit words.

       DSP56K_SET_TX_WSIZE
              sets the transmit word size.  Allowed values are in the range 1 to 4, and is the number of bytes that will be sent
              at a time to the DSP56001.  These data quantities will either be padded with zero bytes, or truncated to  fit  the
              native 24-bit data format of the DSP56001.

       DSP56K_SET_RX_WSIZE
              sets  the  receive  word  size.   Allowed  values are in the range 1 to 4, and is the number of bytes that will be
              received at a time from the DSP56001.  These data quantities will either truncated, or padded  with  a  null  byte
              ('\0') to fit the native 24-bit data format of the DSP56001.

       DSP56K_HOST_FLAGS
              read  and write the host flags.  The host flags are four general-purpose bits that can be read by both the hosting
              computer and the DSP56001.  Bits 0 and 1 can be written by the host, and bits 2  and  3  can  be  written  by  the
              DSP56001.

              To  access  the host flags, the third ioctl(2) argument must be a pointer to a struct dsp56k_host_flags.  If bit 0
              or 1 is set in the dir member, the corresponding bit in out will be written to the host flags.  The state  of  all
              host flags will be returned in the lower four bits of the status member.

       DSP56K_HOST_CMD
              sends  a host command.  Allowed values are in the range 0 to 31, and is a user-defined command handled by the pro-
              gram running in the DSP56001.

FILES
       /dev/dsp56k

SEE ALSO
       linux/include/asm-m68k/dsp56k.h, linux/drivers/char/dsp56k.c, http://dsp56k.nocrew.org/, DSP56000/DSP56001 Digital Signal
       Processor User's Manual

COLOPHON
       This  page  is  part of release 3.25 of the Linux man-pages project.  A description of the project, and information about
       reporting bugs, can be found at http://www.kernel.org/doc/man-pages/.



Linux                                                      2000-03-01                                                  DSP56K(4)