Ameba MicroPython: [RTL8722CSM] [RTL8722DM] SPI
API Documents
Constructors
SPI(unit_id [required], baudrate [optional], polarity [optional], phase [optional], databits [optional], firstbit [optional], miso [optional], mosi [optional], sck [optional], mode [optional])
Create a SPI object and configure it using other parameters. This allows you to then read/write data on the SPI bus.
• unit_id: The unit ID of the hardware SPI, assume default value if left blank
• baudrate: The speed of SPI
• polarity: one of factor determining SPI mode. (deprecated)
• phase: one of factor determining SPI mode. (deprecated)
• databits: number of data bits
• Firstbit: this determine whether first bit is MSB or LSB
• miso: miso pin. (deprecated)
• mosi: mosi pin. (deprecated)
• sck: clock pin. (deprecated)
• mode: either MASTER mode or SLAVE mode
Note: All optional parameters have default values as follows,
| Parameter | Default |
|---|---|
| Baudrate | 2000000 Hz |
| Polarity | Inactive_low |
| Phase | Toggle_middle |
| Databits | 8 |
| Firstbit | MSB |
| Miso | N.A. |
| Mosi | N.A. |
| Sck | N.A. |
| Mode | MASTER |
There is currently 2 set of SPI, they are,
| unit | MOSI | MISO | SCK | CS |
|---|---|---|---|---|
| 0 | PB_18 | PB_19 | PB_20 | PB_21 |
| 1 | PB_4 | PB_5 | PB_6 | PB_7 |
Note: both unit support master mode, but only unit 0 supports slave mode.
Methods
SPI.read()
This method waits and read data received in SPI buffer, then return the data received. Works in both master and slave mode.
SPI.write( value [required])
This method writes an integer value to SPI bus. Works in both master and slave mode.
• value: an integer value to be sent on SPI bus