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PASM SPI object moving up to 32 bytes? — Parallax Forums

PASM SPI object moving up to 32 bytes?

MAElektronikMAElektronik Posts: 96
in Propeller 1

I'm trying to improve speed of SPI byte transfer in an old project. The old SPI PASM object(Propeller SPI engine v1.2) is shifting in selectable bits and I'm shifting in 8 bits at a time using i SPIN repeat loop. But this slows down the data transfer very much.
Old code:
REPEAT thebyte from 0 to bytes-1
BYTE[ptrData][thebyte] := SPIbus.shiftin (PINmosi, PINclk, SPIbus#MSBPRE, 8)

Does anyone have a PASM SPI object where I just can pass the datapointer and number of bytes i want shifted in on this location ?

Comments

  • Wuerfel_21Wuerfel_21 Posts: 5,106
    edited 2021-03-18 11:05

    I once wrote a driver for the 23LC1024 SPI RAM that is decently fast. If you comment out the part where it sends the command (line 118), I think it'll do the trick for you.

    spin
    spin
    23lc1024.spin
    8K
  • MAElektronikMAElektronik Posts: 96

    @Wuerfel_21 said:
    I once wrote a driver for the 23LC1024 SPI RAM that is decently fast. If you comment out the part where it sends the command (line 118), I think it'll do the trick for you.

    Thanks.. I will give it a try tomorrow.

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