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[pic32cz, uart] Add SERCOM UART support. Rename board config variables and PMUX enums #4

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Merged
AlexLanzano merged 1 commit into from
Feb 13, 2026
Merged

[pic32cz, uart] Add SERCOM UART support. Rename board config variables and PMUX enums #4

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1 change: 1 addition & 0 deletions examples/pic32cz/Makefile
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Original file line number Diff line number Diff line change
Expand Up @@ -12,6 +12,7 @@ SOURCE += $(wildcard $(WHAL_DIR)/src/*.c)

SOURCE += $(wildcard $(WHAL_DIR)/src/*/gpio.c)
SOURCE += $(wildcard $(WHAL_DIR)/src/*/clock.c)
SOURCE += $(wildcard $(WHAL_DIR)/src/*/uart.c)
SOURCE += $(wildcard $(WHAL_DIR)/src/*/timer.c)
SOURCE += $(wildcard $(WHAL_DIR)/src/*/supply.c)
SOURCE += $(wildcard $(WHAL_DIR)/src/*/pic32cz_*.c)
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22 changes: 17 additions & 5 deletions examples/pic32cz/main.c
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Original file line number Diff line number Diff line change
Expand Up @@ -36,13 +36,24 @@ void WaitMs(size_t ms)
void main(void)
{
whal_Error err;
uint8_t data[] = "Hello world!\r\n";

err = whal_Clock_Init(&clock);
err = whal_Clock_Init(&g_whalClock);
if (err) {
goto loop;
}

err = whal_Gpio_Init(&gpio);
err = whal_Gpio_Init(&g_whalGpio);
if (err) {
goto loop;
}

err = whal_Uart_Init(&g_whalUart);
if (err) {
goto loop;
}

err = whal_Uart_Send(&g_whalUart, data, sizeof(data));
if (err) {
goto loop;
}
Expand All @@ -55,14 +66,15 @@ void main(void)
whal_Timer_Start(&g_whalTimer);

while (1) {
whal_Gpio_Set(&gpio, 0, 1);
whal_Gpio_Set(&g_whalGpio, 0, 1);

WaitMs(1000);
whal_Gpio_Set(&gpio, 0, 0);

whal_Gpio_Set(&g_whalGpio, 0, 0);

WaitMs(1000);
}


loop:
while (1);
}
56 changes: 41 additions & 15 deletions examples/pic32cz/pic32cz_curiosity_ultra.c
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Original file line number Diff line number Diff line change
@@ -1,17 +1,17 @@
#include <wolfHAL/wolfHAL.h>
#include <wolfHAL/platform/microchip/pic32cz.h>

whal_Supply supply = {
whal_Supply g_whalSupply = {
WHAL_PIC32CZ_SUPPLY_DEVICE,
};

whal_Clock clock = {
whal_Clock g_whalClock = {
WHAL_PIC32CZ_CLOCK_PLL_DEVICE,

.cfg = &(whal_Pic32czClock_Cfg) {
/* 300MHz clock */
.oscCtrlCfg = &(whal_Pic32czClockPll_OscCtrlCfg) {
.supplyCtrl = &supply,
.supplyCtrl = &g_whalSupply,
.supply = &(whal_Pic32czSupc_Supply){WHAL_PIC32CZ_SUPPLY_PLL},

.pllInst = WHAL_PIC32CZ_PLL0,
Expand Down Expand Up @@ -40,25 +40,51 @@ whal_Clock clock = {
},
};

whal_Gpio gpio = {
whal_Gpio g_whalGpio = {
WHAL_PIC32CZ_GPIO_DEVICE,

.cfg = &(whal_Pic32czGpio_Cfg) {
.pinCfgCount = 1,
.pinCfg = &(whal_Pic32czGpio_PinCfg) {
.port = 1,
.pin = 21,
.dir = WHAL_PIC32CZ_DIR_OUTPUT,
.out = 0,
.pinCfgCount = 3,
.pinCfg = (whal_Pic32czGpio_PinCfg[]) {
{ /* LED */
.port = 1,
.pin = 21,
.dir = WHAL_PIC32CZ_DIR_OUTPUT,
.out = 0,
},
{ /* UART TX */
.port = 2,
.pin = 21,
.pmuxEn = 1,
.pmux = WHAL_PIC32CZ_PMUX_SERCOM_ALT,
},
{ /* UART RX */
.port = 2,
.pin = 22,
.pmuxEn = 1,
.pmux = WHAL_PIC32CZ_PMUX_SERCOM_ALT,
},
},
},
};

whal_Pic32czClock_Clk periphClock = {
.gclkPeriphChannel = 0,
.gclkPeriphSrc = 0,
.mclkEnableInst = 0,
.mclkEnableMask = 0,
static whal_Pic32czClock_Clk uartClk = {
.gclkPeriphChannel = 25, /* SERCOM 4 */
.gclkPeriphSrc = 0, /* GEN 0 */
.mclkEnableInst = 1, /* Peripheral BUS Clock Enable Mask1 Register */
.mclkEnableMask = WHAL_MASK(3), /* SERCOM 4 enable mask */
};

whal_Uart g_whalUart = {
WHAL_PIC32CZ_SERCOM4_UART_DEVICE,

.cfg = &(whal_Pic32czUart_Cfg) {
.clkCtrl = &g_whalClock,
.clk = &uartClk,
.baud = WHAL_PIC32CZ_UART_BAUD(115200, 300000000),
.txPad = WHAL_PIC32CZ_UART_TXPO_PAD0,
.rxPad = WHAL_PIC32CZ_UART_RXPO_PAD1,
},
};

whal_Timer g_whalTimer = {
Expand Down
7 changes: 4 additions & 3 deletions examples/pic32cz/pic32cz_curiosity_ultra.h
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Original file line number Diff line number Diff line change
Expand Up @@ -4,9 +4,10 @@
#include <wolfHAL/wolfHAL.h>
#include <wolfHAL/platform/microchip/pic32cz.h>

extern whal_Supply supply;
extern whal_Clock clock;
extern whal_Gpio gpio;
extern whal_Supply g_whalSupply;
extern whal_Clock g_whalClock;
extern whal_Gpio g_whalGpio;
extern whal_Timer g_whalTimer;
extern whal_Uart g_whalUart;

#endif /* WHAL_PIC32CZ_CURIOSITY_ULTRA */
25 changes: 1 addition & 24 deletions src/uart/pic32cz_uart.c
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Original file line number Diff line number Diff line change
Expand Up @@ -97,8 +97,6 @@ whal_Error whal_Pic32czUart_Init(whal_Uart *uartDev)
whal_Error err;
whal_Pic32czUart_Cfg *cfg;
const whal_Regmap *reg;
size_t clockFreq;
uint16_t baudVal;

if (!uartDev) {
return WHAL_EINVAL;
Expand All @@ -113,27 +111,6 @@ whal_Error whal_Pic32czUart_Init(whal_Uart *uartDev)
return err;
}

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Copilot AI Feb 13, 2026

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The software reset (SWRST) that was previously performed at the start of initialization has been removed. Without resetting the SERCOM peripheral, residual configuration from previous operations could cause initialization issues. Consider re-adding the software reset sequence before configuring CTRLA to ensure the peripheral starts in a known clean state, especially after a warm reset or if the peripheral was previously configured.

Suggested change
/* Perform software reset to ensure a clean SERCOM state */
whal_Reg_Update(reg->base, SERCOM_USART_CTRLA_REG,
SERCOM_USART_CTRLA_SWRST,
whal_SetBits(SERCOM_USART_CTRLA_SWRST, 1));
/* Wait for software reset to complete */
whal_Pic32czUart_WaitSync(reg, SERCOM_USART_SYNCBUSY_SWRST);

Copilot uses AI. Check for mistakes.
/* Get clock frequency for baud rate calculation */
err = whal_Clock_GetRate(cfg->clkCtrl, &clockFreq);
if (err != WHAL_SUCCESS) {
return err;
}

/* Software reset the SERCOM */
whal_Reg_Update(reg->base, SERCOM_USART_CTRLA_REG,
SERCOM_USART_CTRLA_SWRST,
whal_SetBits(SERCOM_USART_CTRLA_SWRST, 1));

/* Wait for reset to complete */
whal_Pic32czUart_WaitSync(reg, SERCOM_USART_SYNCBUSY_SWRST);

/*
* Calculate baud value for 16x oversampling arithmetic mode:
* BAUD = 65536 * (1 - 16 * (f_baud / f_ref))
* = 65536 - (65536 * 16 * f_baud) / f_ref
*/
baudVal = (uint16_t)(65536UL - ((65536UL * 16UL * cfg->baud) / clockFreq));

/* Configure CTRLA: internal clock, async mode, LSB first, 16x sampling */
whal_Reg_Update(reg->base, SERCOM_USART_CTRLA_REG,
SERCOM_USART_CTRLA_MODE_MASK |
Expand Down Expand Up @@ -166,7 +143,7 @@ whal_Error whal_Pic32czUart_Init(whal_Uart *uartDev)
/* Set baud rate */
whal_Reg_Update(reg->base, SERCOM_USART_BAUD_REG,
0xFFFF,
baudVal);
cfg->baud);

/* Enable transmitter and receiver */
whal_Reg_Update(reg->base, SERCOM_USART_CTRLB_REG,
Expand Down
29 changes: 15 additions & 14 deletions wolfHAL/gpio/pic32cz_gpio.h
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Expand Up @@ -35,20 +35,21 @@ enum {
* I/O Multiplexing table for valid assignments.
*/
enum {
WHAL_PIC32CZ_PMUX_A = 0x0, /* Peripheral function A */
WHAL_PIC32CZ_PMUX_B = 0x1, /* Peripheral function B */
WHAL_PIC32CZ_PMUX_C = 0x2, /* Peripheral function C */
WHAL_PIC32CZ_PMUX_D = 0x3, /* Peripheral function D */
WHAL_PIC32CZ_PMUX_E = 0x4, /* Peripheral function E */
WHAL_PIC32CZ_PMUX_F = 0x5, /* Peripheral function F */
WHAL_PIC32CZ_PMUX_G = 0x6, /* Peripheral function G */
WHAL_PIC32CZ_PMUX_H = 0x7, /* Peripheral function H */
WHAL_PIC32CZ_PMUX_I = 0x8, /* Peripheral function I */
WHAL_PIC32CZ_PMUX_J = 0x9, /* Peripheral function J */
WHAL_PIC32CZ_PMUX_K = 0xA, /* Peripheral function K */
WHAL_PIC32CZ_PMUX_L = 0xB, /* Peripheral function L */
WHAL_PIC32CZ_PMUX_M = 0xC, /* Peripheral function M */
WHAL_PIC32CZ_PMUX_N = 0xD, /* Peripheral function N */
WHAL_PIC32CZ_PMUX_EIC = 0x0, /* External Interrupts */
WHAL_PIC32CZ_PMUX_AC = 0x1, /* ADC and Analog Comparator */
WHAL_PIC32CZ_PMUX_SERCOM = 0x2, /* SERCOMn (UART, I2C, SPI) */
WHAL_PIC32CZ_PMUX_SERCOM_ALT = 0x3, /* SERCOMn (UART, I2C, SPI) */
WHAL_PIC32CZ_PMUX_EBI = 0x4, /* External Bus Interface */
WHAL_PIC32CZ_PMUX_TCC = 0x5, /* Timer/counter controller */
WHAL_PIC32CZ_PMUX_TCC_ALT_PDEC = 0x6, /* Timer/counter controller
and positional decoder */
WHAL_PIC32CZ_PMUX_COM = 0x7, /* SQI/CAN/USB */
WHAL_PIC32CZ_PMUX_SDMMC = 0x8, /* SD/MMC Host Controller */
WHAL_PIC32CZ_PMUX_SPI_IXS = 0x9, /* SPI_IXS Audio */
WHAL_PIC32CZ_PMUX_PCC = 0xA, /* Parallel Capture Controller */
WHAL_PIC32CZ_PMUX_ETH = 0xB, /* Ethernet */
WHAL_PIC32CZ_PMUX_MISC = 0xC, /* GCLK/CCL/AC Alt */
WHAL_PIC32CZ_PMUX_PTC = 0xD, /* Peripheral Touch Controller */
};

/*
Expand Down
8 changes: 8 additions & 0 deletions wolfHAL/platform/microchip/pic32cz.h
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Original file line number Diff line number Diff line change
Expand Up @@ -4,6 +4,7 @@
#include <wolfHAL/clock/pic32cz_clock.h>
#include <wolfHAL/supply/pic32cz_supc.h>
#include <wolfHAL/gpio/pic32cz_gpio.h>
#include <wolfHAL/uart/pic32cz_uart.h>
#include <wolfHAL/platform/arm/cortex_m7.h>

#define WHAL_PIC32CZ_SUPPLY_DEVICE \
Expand All @@ -27,6 +28,13 @@
}, \
.driver = &whal_Pic32czGpio_Driver

#define WHAL_PIC32CZ_SERCOM4_UART_DEVICE \
.regmap = { \
.base = 0x46004000, \
.size = 0x2000, \
}, \
.driver = &whal_Pic32czUart_Driver

#define WHAL_PIC32CZ_SUPPLY_PLL \
.enableMask = (1 << 18)

Expand Down
3 changes: 3 additions & 0 deletions wolfHAL/uart/pic32cz_uart.h
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Expand Up @@ -11,6 +11,9 @@
* @brief PIC32CZ SERCOM USART driver configuration.
*/

#define WHAL_PIC32CZ_UART_BAUD(freq_baud, freq_ref) \
(65536UL - (65536UL * 16UL * (uint64_t)(freq_baud) / (uint64_t)(freq_ref)))

/*
* @brief PIC32CZ SERCOM USART TX pad output options.
*/
Expand Down