1DSP56K(4) Linux Programmer's Manual DSP56K(4)
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6 dsp56k - DSP56001 interface device
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9 #include <asm/dsp56k.h>
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11 ssize_t read(int fd, void *data, size_t length);
12 ssize_t write(int fd, void *data, size_t length);
13 int ioctl(int fd, DSP56K_UPLOAD, struct dsp56k_upload *program);
14 int ioctl(int fd, DSP56K_SET_TX_WSIZE, int wsize);
15 int ioctl(int fd, DSP56K_SET_RX_WSIZE, int wsize);
16 int ioctl(int fd, DSP56K_HOST_FLAGS, struct dsp56k_host_flags *flags);
17 int ioctl(int fd, DSP56K_HOST_CMD, int cmd);
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20 The dsp56k device is a character device with major number 55 and minor
21 number 0.
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24 The Motorola DSP56001 is a fully programmable 24-bit digital signal
25 processor found in Atari Falcon030-compatible computers. The dsp56k
26 special file is used to control the DSP56001, and to send and receive
27 data using the bi-directional handshaked host port.
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29 To send a data stream to the signal processor, use write() to the
30 device, and read() to receive processed data. The data can be sent or
31 received in 8, 16, 24, or 32-bit quantities on the host side, but will
32 always be seen as 24-bit quantities in the DSP56001.
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34 The following ioctl(2) calls are used to control the dsp56k device:
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36 DSP56K_UPLOAD
37 resets the DSP56001 and uploads a program. The third ioctl()
38 argument must be a pointer to a struct dsp56k_binary with mem‐
39 bers bin pointing to a DSP56001 binary program, and len set to
40 the length of the program, counted in 24-bit words.
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42 DSP56K_SET_TX_WSIZE
43 sets the transmit word size. Allowed values are in the range 1
44 to 4, and is the number of bytes that will be sent at a time to
45 the DSP56001. These data quantities will either be padded with
46 zero bytes, or truncated to fit the native 24-bit data format of
47 the DSP56001.
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49 DSP56K_SET_RX_WSIZE
50 sets the receive word size. Allowed values are in the range 1
51 to 4, and is the number of bytes that will be received at a time
52 from the DSP56001. These data quantities will either truncated,
53 or padded with a null byte ('\0') to fit the native 24-bit data
54 format of the DSP56001.
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56 DSP56K_HOST_FLAGS
57 read and write the host flags. The host flags are four general-
58 purpose bits that can be read by both the hosting computer and
59 the DSP56001. Bits 0 and 1 can be written by the host, and bits
60 2 and 3 can be written by the DSP56001.
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62 To access the host flags, the third ioctl() argument must be a
63 pointer to a struct dsp56k_host_flags. If bit 0 or 1 is set in
64 the dir member, the corresponding bit in out will be written to
65 the host flags. The state of all host flags will be returned in
66 the lower four bits of the status member.
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68 DSP56K_HOST_CMD
69 sends a host command. Allowed values are in the range 0 to 31,
70 and is a user-defined command handled by the program running in
71 the DSP56001.
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74 /dev/dsp56k
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77 Fredrik Noring <noring@nocrew.org>, lars brinkhoff <lars@nocrew.org>,
78 Tomas Berndtsson <tomas@nocrew.org>.
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81 linux/include/asm-m68k/dsp56k.h, linux/drivers/char/dsp56k.c,
82 http://dsp56k.nocrew.org/, DSP56000/DSP56001 Digital Signal Processor
83 User's Manual
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87Special files 2000-03-01 DSP56K(4)