man4/dsp56k.4

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   2 .\" Copyright (c) 2000 lars brinkhoff <lars@nocrew.org>
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  23 .\" Modified, Thu Jan 27 19:16:19 CET 2000, lars@nocrew.org
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  25 .TH DSP56K 4 2012-08-05 "Linux" "Linux Programmer's Manual"
  26 .SH NAME
  27 dsp56k \- DSP56001 interface device
  28 .SH SYNOPSIS
  29 .nf
  30 #include <asm/dsp56k.h>
  31 .sp
  32 .BI "ssize_t read(int " fd ", void *" data ", size_t " length );
  33 .BI "ssize_t write(int " fd ", void *" data ", size_t " length );
  34
  35 .BI "int ioctl(int " fd ", DSP56K_UPLOAD, struct dsp56k_upload *" program );
  36 .BI "int ioctl(int " fd ", DSP56K_SET_TX_WSIZE, int " wsize );
  37 .BI "int ioctl(int " fd ", DSP56K_SET_RX_WSIZE, int " wsize );
  38 .BI "int ioctl(int " fd ", DSP56K_HOST_FLAGS, struct dsp56k_host_flags *" flags );
  39 .BI "int ioctl(int " fd ", DSP56K_HOST_CMD, int " cmd );
  40 .fi
  41 .SH CONFIGURATION
  42 The dsp56k device is a character device with major number 55 and minor
  43 number 0.
  44 .SH DESCRIPTION
  45 The Motorola DSP56001 is a fully programmable 24-bit digital signal
  46 processor found in Atari Falcon030-compatible computers.
  47 The \fIdsp56k\fP special file is used to control the DSP56001, and
  48 to send and receive data using the bidirectional handshaked host
  49 port.
  50 .PP
  51 To send a data stream to the signal processor, use
  52 .BR write (2)
  53 to the
  54 device, and
  55 .BR read (2)
  56 to receive processed data.
  57 The data can be sent or
  58 received in 8, 16, 24, or 32-bit quantities on the host side, but will
  59 always be seen as 24-bit quantities in the DSP56001.
  60 .PP
  61 The following
  62 .BR ioctl (2)
  63 calls are used to control the
  64 \fIdsp56k\fP device:
  65 .IP \fBDSP56K_UPLOAD\fP
  66 resets the DSP56001 and uploads a program.
  67 The third
  68 .BR ioctl (2)
  69 argument must be a pointer to a \fIstruct dsp56k_binary\fP with members
  70 \fIbin\fP pointing to a DSP56001 binary program, and \fIlen\fP set to
  71 the length of the program, counted in 24-bit words.
  72 .IP \fBDSP56K_SET_TX_WSIZE\fP
  73 sets the transmit word size.
  74 Allowed values are in the range 1 to 4,
  75 and is the number of bytes that will be sent at a time to the
  76 DSP56001.
  77 These data quantities will either be padded with zero
  78 bytes, or truncated to fit the native 24-bit data format of the
  79 DSP56001.
  80 .IP \fBDSP56K_SET_RX_WSIZE\fP
  81 sets the receive word size.
  82 Allowed values are in the range 1 to 4,
  83 and is the number of bytes that will be received at a time from the
  84 DSP56001.
  85 These data quantities will either truncated, or padded with
  86 a null byte (\(aq\\0\(aq) to fit the native 24-bit data format of the DSP56001.
  87 .IP \fBDSP56K_HOST_FLAGS\fP
  88 read and write the host flags.
  89 The host flags are four
  90 general-purpose bits that can be read by both the hosting computer and
  91 the DSP56001.
  92 Bits 0 and 1 can be written by the host, and bits 2 and
  93 3 can be written by the DSP56001.
  94
  95 To access the host flags, the third
  96 .BR ioctl (2)
  97 argument must be a pointer
  98 to a \fIstruct dsp56k_host_flags\fP.
  99 If bit 0 or 1 is set in the
 100 \fIdir\fP member, the corresponding bit in \fIout\fP will be written
 101 to the host flags.
 102 The state of all host flags will be returned in
 103 the lower four bits of the \fIstatus\fP member.
 104 .IP \fBDSP56K_HOST_CMD\fP
 105 sends a host command.
 106 Allowed values are in the range 0 to 31, and is a
 107 user-defined command handled by the program running in the DSP56001.
 108 .SH FILES
 109 /dev/dsp56k
 110 .\" .SH AUTHORS
 111 .\" Fredrik Noring <noring@nocrew.org>, lars brinkhoff <lars@nocrew.org>,
 112 .\" Tomas Berndtsson <tomas@nocrew.org>.
 113 .SH SEE ALSO
 114 .IR linux/include/asm-m68k/dsp56k.h ,
 115 .IR linux/drivers/char/dsp56k.c ,
 116 .UR http://dsp56k.nocrew.org/
 117 .UE ,
 118 DSP56000/DSP56001 Digital Signal Processor User's Manual