c4e58eaa98
New keyword option in constructor and init() method is "dma=<bool>". DMA is now disabled by default for I2C transfers because it currently does not handle I2C bus errors very well (eg if slave device doesn't ACK or NACK correctly during a transfer).
51 lines
1.1 KiB
Python
51 lines
1.1 KiB
Python
# test I2C errors, with polling (disabled irqs) and DMA
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import pyb
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from pyb import I2C
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# init accelerometer
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pyb.Accel()
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# get I2C bus
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i2c = I2C(1, I2C.MASTER, dma=True)
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# test polling mem_read
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pyb.disable_irq()
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i2c.mem_read(1, 76, 0x0a) # should succeed
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pyb.enable_irq()
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try:
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pyb.disable_irq()
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i2c.mem_read(1, 77, 0x0a) # should fail
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except OSError as e:
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pyb.enable_irq()
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print(repr(e))
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i2c.mem_read(1, 76, 0x0a) # should succeed
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# test polling mem_write
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pyb.disable_irq()
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i2c.mem_write(1, 76, 0x0a) # should succeed
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pyb.enable_irq()
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try:
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pyb.disable_irq()
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i2c.mem_write(1, 77, 0x0a) # should fail
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except OSError as e:
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pyb.enable_irq()
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print(repr(e))
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i2c.mem_write(1, 76, 0x0a) # should succeed
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# test DMA mem_read
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i2c.mem_read(1, 76, 0x0a) # should succeed
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try:
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i2c.mem_read(1, 77, 0x0a) # should fail
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except OSError as e:
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print(repr(e))
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i2c.mem_read(1, 76, 0x0a) # should succeed
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# test DMA mem_write
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i2c.mem_write(1, 76, 0x0a) # should succeed
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try:
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i2c.mem_write(1, 77, 0x0a) # should fail
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except OSError as e:
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print(repr(e))
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i2c.mem_write(1, 76, 0x0a) # should succeed
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