nrf: add support for nrf52833

This adds preliminary support for the nRF52833, which is a variant of
the nRF52840 with half the RAM, half the flash, and fewer peripherals.

Signed-off-by: Sean Cross <sean@xobs.io>

4 files changed, 200 insertions, 0 deletions

diff --git a/ports/nrf/peripherals/nrf/nrf52833/pins.c b/ports/nrf/peripherals/nrf/nrf52833/pins.c
new file mode 100644
index 000000000..cdd4959cb
--- /dev/null
+++ b/ports/nrf/peripherals/nrf/nrf52833/pins.c
@@ -0,0 +1,72 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2018 Dan Halbert for Adafruit Industries
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "py/obj.h"
+#include "py/mphal.h"
+#include "nrf/pins.h"
+
+const mcu_pin_obj_t pin_P0_00 = PIN(P0_00, 0, 0, 0);
+const mcu_pin_obj_t pin_P0_01 = PIN(P0_01, 0, 1, 0);
+const mcu_pin_obj_t pin_P0_02 = PIN(P0_02, 0, 2, SAADC_CH_PSELP_PSELP_AnalogInput0);
+const mcu_pin_obj_t pin_P0_03 = PIN(P0_03, 0, 3, SAADC_CH_PSELP_PSELP_AnalogInput1);
+const mcu_pin_obj_t pin_P0_04 = PIN(P0_04, 0, 4, SAADC_CH_PSELP_PSELP_AnalogInput2);
+const mcu_pin_obj_t pin_P0_05 = PIN(P0_05, 0, 5, SAADC_CH_PSELP_PSELP_AnalogInput3);
+const mcu_pin_obj_t pin_P0_06 = PIN(P0_06, 0, 6, 0);
+const mcu_pin_obj_t pin_P0_07 = PIN(P0_07, 0, 7, 0);
+const mcu_pin_obj_t pin_P0_08 = PIN(P0_08, 0, 8, 0);
+const mcu_pin_obj_t pin_P0_09 = PIN(P0_09, 0, 9, 0);
+const mcu_pin_obj_t pin_P0_10 = PIN(P0_10, 0, 10, 0);
+const mcu_pin_obj_t pin_P0_11 = PIN(P0_11, 0, 11, 0);
+const mcu_pin_obj_t pin_P0_12 = PIN(P0_12, 0, 12, 0);
+const mcu_pin_obj_t pin_P0_13 = PIN(P0_13, 0, 13, 0);
+const mcu_pin_obj_t pin_P0_14 = PIN(P0_14, 0, 14, 0);
+const mcu_pin_obj_t pin_P0_15 = PIN(P0_15, 0, 15, 0);
+const mcu_pin_obj_t pin_P0_16 = PIN(P0_16, 0, 16, 0);
+const mcu_pin_obj_t pin_P0_17 = PIN(P0_17, 0, 17, 0);
+const mcu_pin_obj_t pin_P0_18 = PIN(P0_18, 0, 18, 0);
+const mcu_pin_obj_t pin_P0_19 = PIN(P0_19, 0, 19, 0);
+const mcu_pin_obj_t pin_P0_20 = PIN(P0_20, 0, 20, 0);
+const mcu_pin_obj_t pin_P0_21 = PIN(P0_21, 0, 21, 0);
+const mcu_pin_obj_t pin_P0_22 = PIN(P0_22, 0, 22, 0);
+const mcu_pin_obj_t pin_P0_23 = PIN(P0_23, 0, 23, 0);
+const mcu_pin_obj_t pin_P0_24 = PIN(P0_24, 0, 24, 0);
+const mcu_pin_obj_t pin_P0_25 = PIN(P0_25, 0, 25, 0);
+const mcu_pin_obj_t pin_P0_26 = PIN(P0_26, 0, 26, 0);
+const mcu_pin_obj_t pin_P0_27 = PIN(P0_27, 0, 27, 0);
+const mcu_pin_obj_t pin_P0_28 = PIN(P0_28, 0, 28, SAADC_CH_PSELP_PSELP_AnalogInput4);
+const mcu_pin_obj_t pin_P0_29 = PIN(P0_29, 0, 29, SAADC_CH_PSELP_PSELP_AnalogInput5);
+const mcu_pin_obj_t pin_P0_30 = PIN(P0_30, 0, 30, SAADC_CH_PSELP_PSELP_AnalogInput6);
+const mcu_pin_obj_t pin_P0_31 = PIN(P0_31, 0, 31, SAADC_CH_PSELP_PSELP_AnalogInput7);
+const mcu_pin_obj_t pin_P1_00 = PIN(P1_00, 1, 0, 0);
+const mcu_pin_obj_t pin_P1_01 = PIN(P1_01, 1, 1, 0);
+const mcu_pin_obj_t pin_P1_02 = PIN(P1_02, 1, 2, 0);
+const mcu_pin_obj_t pin_P1_03 = PIN(P1_03, 1, 3, 0);
+const mcu_pin_obj_t pin_P1_04 = PIN(P1_04, 1, 4, 0);
+const mcu_pin_obj_t pin_P1_05 = PIN(P1_05, 1, 5, 0);
+const mcu_pin_obj_t pin_P1_06 = PIN(P1_06, 1, 6, 0);
+const mcu_pin_obj_t pin_P1_07 = PIN(P1_07, 1, 7, 0);
+const mcu_pin_obj_t pin_P1_08 = PIN(P1_08, 1, 8, 0);
+const mcu_pin_obj_t pin_P1_09 = PIN(P1_09, 1, 9, 0);
diff --git a/ports/nrf/peripherals/nrf/nrf52833/pins.h b/ports/nrf/peripherals/nrf/nrf52833/pins.h
new file mode 100644
index 000000000..44baa315b
--- /dev/null
+++ b/ports/nrf/peripherals/nrf/nrf52833/pins.h
@@ -0,0 +1,73 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2018 by Dan Halbert for Adafruit Industries
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#ifndef MICROPY_INCLUDED_NRF_PERIPHERALS_NRF52833_PINS_H
+#define MICROPY_INCLUDED_NRF_PERIPHERALS_NRF52833_PINS_H
+
+extern const mcu_pin_obj_t pin_P0_00;
+extern const mcu_pin_obj_t pin_P0_01;
+extern const mcu_pin_obj_t pin_P0_02;
+extern const mcu_pin_obj_t pin_P0_03;
+extern const mcu_pin_obj_t pin_P0_04;
+extern const mcu_pin_obj_t pin_P0_05;
+extern const mcu_pin_obj_t pin_P0_06;
+extern const mcu_pin_obj_t pin_P0_07;
+extern const mcu_pin_obj_t pin_P0_08;
+extern const mcu_pin_obj_t pin_P0_09;
+extern const mcu_pin_obj_t pin_P0_10;
+extern const mcu_pin_obj_t pin_P0_11;
+extern const mcu_pin_obj_t pin_P0_12;
+extern const mcu_pin_obj_t pin_P0_13;
+extern const mcu_pin_obj_t pin_P0_14;
+extern const mcu_pin_obj_t pin_P0_15;
+extern const mcu_pin_obj_t pin_P0_16;
+extern const mcu_pin_obj_t pin_P0_17;
+extern const mcu_pin_obj_t pin_P0_18;
+extern const mcu_pin_obj_t pin_P0_19;
+extern const mcu_pin_obj_t pin_P0_20;
+extern const mcu_pin_obj_t pin_P0_21;
+extern const mcu_pin_obj_t pin_P0_22;
+extern const mcu_pin_obj_t pin_P0_23;
+extern const mcu_pin_obj_t pin_P0_24;
+extern const mcu_pin_obj_t pin_P0_25;
+extern const mcu_pin_obj_t pin_P0_26;
+extern const mcu_pin_obj_t pin_P0_27;
+extern const mcu_pin_obj_t pin_P0_28;
+extern const mcu_pin_obj_t pin_P0_29;
+extern const mcu_pin_obj_t pin_P0_30;
+extern const mcu_pin_obj_t pin_P0_31;
+extern const mcu_pin_obj_t pin_P1_00;
+extern const mcu_pin_obj_t pin_P1_01;
+extern const mcu_pin_obj_t pin_P1_02;
+extern const mcu_pin_obj_t pin_P1_03;
+extern const mcu_pin_obj_t pin_P1_04;
+extern const mcu_pin_obj_t pin_P1_05;
+extern const mcu_pin_obj_t pin_P1_06;
+extern const mcu_pin_obj_t pin_P1_07;
+extern const mcu_pin_obj_t pin_P1_08;
+extern const mcu_pin_obj_t pin_P1_09;
+
+#endif // MICROPY_INCLUDED_NRF_PERIPHERALS_NRF52833_PINS_H
diff --git a/ports/nrf/peripherals/nrf/nrf52833/power.c b/ports/nrf/peripherals/nrf/nrf52833/power.c
new file mode 100644
index 000000000..d64c536bb
--- /dev/null
+++ b/ports/nrf/peripherals/nrf/nrf52833/power.c
@@ -0,0 +1,50 @@
+/*
+ * This file is part of the Micro Python project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2018 Dan Halbert for Adafruit Industries
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "nrfx.h"
+#include "hal/nrf_nvmc.h"
+
+void nrf_peripherals_power_init(void) {
+    // Set GPIO reference voltage to 3.3V if it isn't already. REGOUT0 will get reset to 0xfffffff
+    // if flash is erased, which sets the default to 1.8V
+    // This matters only when "high voltage mode" is enabled, which is true on the PCA10059,
+    // and might be true on other boards.
+    if (NRF_UICR->REGOUT0 == 0xffffffff && NRF_POWER->MAINREGSTATUS & 1) {
+        // Expand what nrf_nvmc_word_write() did.
+        // It's missing from nrfx V2.0.0, and nrfx_nvmc_word_write() does bounds
+        // checking which prevents writes to UICR.
+        // Reported: https://devzone.nordicsemi.com/f/nordic-q-a/57243/nrfx_nvmc-h-api-cannot-write-to-uicr
+        NRF_NVMC->CONFIG = NRF_NVMC_MODE_WRITE;
+        while (!(NRF_NVMC->READY & NVMC_READY_READY_Msk)) {}
+        NRF_UICR->REGOUT0 = UICR_REGOUT0_VOUT_3V3 << UICR_REGOUT0_VOUT_Pos;
+        __DMB();
+        while (NRF_NVMC->READY == NVMC_READY_READY_Busy) {}
+        NRF_NVMC->CONFIG = NRF_NVMC_MODE_READONLY;
+
+        // Must reset to enable change.
+        NVIC_SystemReset();
+    }
+}
diff --git a/ports/nrf/peripherals/nrf/pins.h b/ports/nrf/peripherals/nrf/pins.h
index 3a4c99579..efdc8892a 100644
--- a/ports/nrf/peripherals/nrf/pins.h
+++ b/ports/nrf/peripherals/nrf/pins.h
@@ -61,4 +61,9 @@ extern const mp_obj_type_t mcu_pin_type;
 #include "nrf52840/pins.h"
 #endif
 
+// Choose based on chip, but not specifically revision (e.g., not NRF52840_XXAA)
+#ifdef NRF52833
+#include "nrf52833/pins.h"
+#endif
+
 #endif // __MICROPY_INCLUDED_NRF_PERIPHERALS_PINS_H__