18 lines
887 B
Plaintext
18 lines
887 B
Plaintext
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README
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This example program demonstrates SPI transceive with DMA on Lisa/M 2.0 board
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(http://paparazzi.enac.fr/wiki/Lisa/M_v20 for details).
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The terminal settings for the receiving device/PC are 9600 8n1.
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The example expects a loopback connection between the MISO and MOSI pins on
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SPI1. The DRDY and SS pins (on the Lisa/M v2.0 SPI1 connector) are used as
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GPIO to time the tx and rx ISRs, respectively. Use a scope or logic analyzer.
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The tx length is incremented, followed by the rx length, after which the tx is
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decremented, then the rx is decremented. This is repeated in a loop. In this
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example, rx lengths longer than tx lengths are handled by using two dma transmits
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one after the other, handled inside the tx dma ISR.
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