diff --git a/board/hammer/gpio.inc b/board/hammer/gpio.inc
index bc8dbdfd0b..6ab26af4ec 100644
--- a/board/hammer/gpio.inc
+++ b/board/hammer/gpio.inc
@@ -52,7 +52,7 @@ GPIO(WP_L,			PIN(A, 13), GPIO_INPUT)
 /* Unimplemented signals since we are not an EC */
 UNIMPLEMENTED(ENTERING_RW)
 
-ALTERNATE(PIN_MASK(A, 0x0600), 1, MODULE_UART, 0) /* USART1: PA09/PA10 - Servo stm32 console UART */
+ALTERNATE(PIN_MASK(A, 0x0600), 1, MODULE_UART, GPIO_PULL_UP) /* USART1: PA09/PA10 - Servo stm32 console UART */
 
 ALTERNATE(PIN_MASK(B, 0x00c0), 1, MODULE_I2C, 0) /* I2C MASTER:PB6/7 GPIO_ODR_HIGH */