diff --git a/cores/esp32/esp32-hal-uart.c b/cores/esp32/esp32-hal-uart.c
index 91d3adea4f4..0aa5090b6bd 100644
--- a/cores/esp32/esp32-hal-uart.c
+++ b/cores/esp32/esp32-hal-uart.c
@@ -375,7 +375,7 @@ bool uartSetHwFlowCtrlMode(uart_t *uart, uart_hw_flowcontrol_t mode, uint8_t thr
 
 // This helper function will return true if a new IDF UART driver needs to be restarted and false if the current one can continue its execution
 bool _testUartBegin(
-  uint8_t uart_nr, uint32_t baudrate, uint32_t config, int8_t rxPin, int8_t txPin, uint16_t rx_buffer_size, uint16_t tx_buffer_size, bool inverted,
+  uint8_t uart_nr, uint32_t baudrate, uint32_t config, int8_t rxPin, int8_t txPin, uint32_t rx_buffer_size, uint32_t tx_buffer_size, bool inverted,
   uint8_t rxfifo_full_thrhd
 ) {
   if (uart_nr >= SOC_UART_NUM) {
@@ -397,7 +397,7 @@ bool _testUartBegin(
 }
 
 uart_t *uartBegin(
-  uint8_t uart_nr, uint32_t baudrate, uint32_t config, int8_t rxPin, int8_t txPin, uint16_t rx_buffer_size, uint16_t tx_buffer_size, bool inverted,
+  uint8_t uart_nr, uint32_t baudrate, uint32_t config, int8_t rxPin, int8_t txPin, uint32_t rx_buffer_size, uint32_t tx_buffer_size, bool inverted,
   uint8_t rxfifo_full_thrhd
 ) {
   if (uart_nr >= SOC_UART_NUM) {
diff --git a/cores/esp32/esp32-hal-uart.h b/cores/esp32/esp32-hal-uart.h
index 1cd5411bf25..402b5785915 100644
--- a/cores/esp32/esp32-hal-uart.h
+++ b/cores/esp32/esp32-hal-uart.h
@@ -33,11 +33,11 @@ struct uart_struct_t;
 typedef struct uart_struct_t uart_t;
 
 bool _testUartBegin(
-  uint8_t uart_nr, uint32_t baudrate, uint32_t config, int8_t rxPin, int8_t txPin, uint16_t rx_buffer_size, uint16_t tx_buffer_size, bool inverted,
+  uint8_t uart_nr, uint32_t baudrate, uint32_t config, int8_t rxPin, int8_t txPin, uint32_t rx_buffer_size, uint32_t tx_buffer_size, bool inverted,
   uint8_t rxfifo_full_thrhd
 );
 uart_t *uartBegin(
-  uint8_t uart_nr, uint32_t baudrate, uint32_t config, int8_t rxPin, int8_t txPin, uint16_t rx_buffer_size, uint16_t tx_buffer_size, bool inverted,
+  uint8_t uart_nr, uint32_t baudrate, uint32_t config, int8_t rxPin, int8_t txPin, uint32_t rx_buffer_size, uint32_t tx_buffer_size, bool inverted,
   uint8_t rxfifo_full_thrhd
 );
 void uartEnd(uint8_t uart_num);