ad53xx: move 8 bit shift out of ad53xx protocol funcs

That's specific to the SPI bus, not to the ad53xx.
This commit is contained in:
Robert Jördens 2018-03-24 15:15:56 +01:00
parent 08326c5727
commit 2cf414a480

View File

@ -49,10 +49,9 @@ def ad53xx_cmd_write_ch(channel, value, op):
:param op: The channel register to write to, one of
:const:`AD53XX_CMD_DATA`, :const:`AD53XX_CMD_OFFSET` or
:const:`AD53XX_CMD_GAIN`.
:return: The 24-bit word to be written to the DAC, aligned as the 24 MSB of
a 32-bit integer, ready to be transferred directly by the SPI core.
:return: The 24-bit word to be written to the DAC
"""
return (op | ((channel & 0x3f) + 8) << 16 | (value & 0xffff)) << 8
return op | ((channel & 0x3f) + 8) << 16 | (value & 0xffff)
@portable
@ -64,11 +63,10 @@ def ad53xx_cmd_read_ch(channel, op):
:param op: The channel register to read, one of
:const:`AD53XX_CMD_DATA`, :const:`AD53XX_CMD_OFFSET` or
:const:`AD53XX_CMD_GAIN`
:return: The 24-bit word to be written to the DAC, aligned as the 24 MSB of
a 32-bit integer, ready to be transferred directly by the SPI core.
:return: The 24-bit word to be written to the DAC
"""
return (AD53XX_CMD_SPECIAL | AD53XX_SPECIAL_READ | op |
(((channel & 0x3f) + 8) << 7)) << 8
(((channel & 0x3f) + 8) << 7))
@portable
@ -163,7 +161,7 @@ class AD53xx:
:const:`AD53XX_READ_GAIN` (default: :const:`AD53XX_READ_X1A`).
:return: The 16 bit register value
"""
self.bus.write(ad53xx_cmd_read_ch(channel, op))
self.bus.write(ad53xx_cmd_read_ch(channel, op) << 8)
self.bus.set_config_mu(SPI_AD53XX_CONFIG | spi.SPI_INPUT, 24,
self.div_read, self.chip_select)
delay(270*ns) # t_21 min sync high in readback
@ -197,7 +195,8 @@ class AD53xx:
:param gain: 16-bit gain register value (default: 0xffff)
"""
self.bus.write(ad53xx_cmd_write_ch(channel, gain, AD53XX_CMD_GAIN))
self.bus.write(
ad53xx_cmd_write_ch(channel, gain, AD53XX_CMD_GAIN) << 8)
@kernel
def write_offset_mu(self, channel, offset=0x8000):
@ -208,7 +207,8 @@ class AD53xx:
:param offset: 16-bit offset register value (default: 0x8000)
"""
self.bus.write(ad53xx_cmd_write_ch(channel, offset, AD53XX_CMD_OFFSET))
self.bus.write(
ad53xx_cmd_write_ch(channel, offset, AD53XX_CMD_OFFSET) << 8)
@kernel
def write_offset(self, channel, voltage):
@ -230,7 +230,8 @@ class AD53xx:
The DAC output is not updated until LDAC is pulsed (see :meth load:).
This method advances the timeline by the duration of one SPI transfer.
"""
self.bus.write(ad53xx_cmd_write_ch(channel, value, AD53XX_CMD_DATA))
self.bus.write(
ad53xx_cmd_write_ch(channel, value, AD53XX_CMD_DATA) << 8)
@kernel
def write_dac(self, channel, voltage):