rework mcp4822 module from mtm_hardware.DACOut

Author: todbot

locale/circuitpython.pot

@@ -5,5 +5,24 @@
 // SPDX-License-Identifier: MIT
 
 #include "supervisor/board.h"
+#include "shared-bindings/mcp4822/MCP4822.h"
+#include "shared-bindings/microcontroller/Pin.h"
+#include "peripherals/pins.h"
+#include "py/runtime.h"
+
+// board.DAC() — factory function that constructs an mcp4822.MCP4822 with
+// the MTM Workshop Computer's DAC pins (GP18=SCK, GP19=SDI, GP21=CS).
+static mp_obj_t board_dac_factory(void) {
+    mcp4822_mcp4822_obj_t *dac = mp_obj_malloc_with_finaliser(
+        mcp4822_mcp4822_obj_t, &mcp4822_mcp4822_type);
+    common_hal_mcp4822_mcp4822_construct(
+        dac,
+        &pin_GPIO18,   // clock (SCK)
+        &pin_GPIO19,   // mosi (SDI)
+        &pin_GPIO21,   // cs
+        1);            // gain 1x
+    return MP_OBJ_FROM_PTR(dac);
+}
+MP_DEFINE_CONST_FUN_OBJ_0(board_dac_obj, board_dac_factory);
 
 // Use the MP_WEAK supervisor/shared/board.c versions of routines not defined here.

ports/raspberrypi/boards/mtm_computer/board.c

@@ -11,7 +11,4 @@ EXTERNAL_FLASH_DEVICES = "W25Q16JVxQ"
 CIRCUITPY_AUDIOEFFECTS = 1
 CIRCUITPY_IMAGECAPTURE = 0
 CIRCUITPY_PICODVI = 0
-
-SRC_C += \
-	boards/$(BOARD)/module/mtm_hardware.c \
-	boards/$(BOARD)/module/DACOut.c
+CIRCUITPY_MCP4822 = 1

ports/raspberrypi/boards/mtm_computer/module/DACOut.h

@@ -6,6 +6,8 @@
 
 #include "shared-bindings/board/__init__.h"
 
+extern const mp_obj_fun_builtin_fixed_t board_dac_obj;
+
 static const mp_rom_map_elem_t board_module_globals_table[] = {
     CIRCUITPYTHON_BOARD_DICT_STANDARD_ITEMS
 
@@ -21,7 +23,6 @@ static const mp_rom_map_elem_t board_module_globals_table[] = {
     { MP_ROM_QSTR(MP_QSTR_PULSE_2_IN), MP_ROM_PTR(&pin_GPIO3) },
     { MP_ROM_QSTR(MP_QSTR_GP3), MP_ROM_PTR(&pin_GPIO3) },
 
-
     { MP_ROM_QSTR(MP_QSTR_NORM_PROBE), MP_ROM_PTR(&pin_GPIO4) },
     { MP_ROM_QSTR(MP_QSTR_GP4), MP_ROM_PTR(&pin_GPIO4) },
 
@@ -105,6 +106,9 @@ static const mp_rom_map_elem_t board_module_globals_table[] = {
     { MP_ROM_QSTR(MP_QSTR_A3), MP_ROM_PTR(&pin_GPIO29) },
     { MP_ROM_QSTR(MP_QSTR_GP29), MP_ROM_PTR(&pin_GPIO29) },
 
+    // Factory function: dac = board.DAC() returns a configured mcp4822.MCP4822
+    { MP_ROM_QSTR(MP_QSTR_DAC), MP_ROM_PTR(&board_dac_obj) },
+
     // { MP_ROM_QSTR(MP_QSTR_EEPROM_I2C), MP_ROM_PTR(&board_i2c_obj) },
 };
 MP_DEFINE_CONST_DICT(board_module_globals, board_module_globals_table);