From cc87363234e22b2ba3a1b91f73f3a3b3f16d01df Mon Sep 17 00:00:00 2001 From: Dan Halbert Date: Tue, 30 Jan 2018 14:31:20 -0500 Subject: [PATCH] documentation: caution on SPI clock speed for SAMD21 --- shared-bindings/busio/SPI.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/shared-bindings/busio/SPI.c b/shared-bindings/busio/SPI.c index d68b61d9b4..c2889bb129 100644 --- a/shared-bindings/busio/SPI.c +++ b/shared-bindings/busio/SPI.c @@ -140,6 +140,9 @@ static void check_lock(busio_spi_obj_t *self) { //| :param int baudrate: the desired clock rate in Hertz. The actual clock rate may be higher or lower //| due to the granularity of available clock settings. //| Check the `frequency` attribute for the actual clock rate. +//| **Note:** on the SAMD21, it is possible to set the baud rate to 24 MHz, but that +//| speed is not guaranteed to work. 12 MHz is the next available lower speed, and is +//| within spec for the SAMD21. //| :param int polarity: the base state of the clock line (0 or 1) //| :param int phase: the edge of the clock that data is captured. First (0) //| or second (1). Rising or falling depends on clock polarity.