Problem driving PORT C1 High - suspect bad chip or device configuration error.
I have a legacy design with a STM8L052C6 MCU. There is a 4x3 matrix keypad. I am trying to drive the Rows and scan the columns. The C1 port only rises to about 0.5V when I set the pin HIGH. Is there something I am missing.
There are three ports set as PP_HIGH_FAST outputs (Ports A3 and E7 work as expected. Port C1 exhibits the 0.5V high. VDD is 3V. There is a 510K resistor pull up on this pin in the design that is not on the other pins. I am recreating the source code for the board and am not sure why the resistor is there or why I can't get C1 to go full high. I have tried OD as well as the SLOW options. BTW what is the difference between the LOW and HIGH options in the peripheral driver GPIO_Mode_TypeDef options.
// Matrix Keypad Scanner Drivers
#define KP_ROW1_PORT GPIOA
#define KP_ROW1_PIN GPIO_Pin_3
#define KP_ROW2_PORT GPIOE
#define KP_ROW2_PIN GPIO_Pin_7
#define KP_ROW3_PORT GPIOC
#define KP_ROW3_PIN GPIO_Pin_1
// Matrix Keypad Scanner Receivers
#define KP_COL1_PORT GPIOC
#define KP_COL1_PIN GPIO_Pin_4
#define KP_COL2_PORT GPIOC
#define KP_COL2_PIN GPIO_Pin_7
#define KP_COL3_PORT GPIOE
#define KP_COL3_PIN GPIO_Pin_6
#define KP_COL4_PORT GPIOA
#define KP_COL4_PIN GPIO_Pin_2
/* Initialize Keypad Pins */
// Driver Pins
GPIO_Init(KP_ROW1_PORT, KP_ROW1_PIN, GPIO_Mode_Out_PP_High_Fast);
GPIO_Init(KP_ROW2_PORT, KP_ROW2_PIN, GPIO_Mode_Out_PP_High_Fast);
GPIO_Init(KP_ROW3_PORT, KP_ROW3_PIN, GPIO_Mode_Out_PP_High_Fast);
// GPIO_ExternalPullUpConfig(KP_ROW3_PORT, KP_ROW3_PIN, ENABLE);
// Receiver Pins
GPIO_Init(KP_COL1_PORT, KP_COL1_PIN, GPIO_Mode_In_FL_No_IT);
GPIO_Init(KP_COL2_PORT, KP_COL2_PIN, GPIO_Mode_In_FL_No_IT);
GPIO_Init(KP_COL3_PORT, KP_COL3_PIN, GPIO_Mode_In_FL_No_IT);
GPIO_Init(KP_COL4_PORT, KP_COL4_PIN, GPIO_Mode_In_FL_No_IT);
// ==============
Here is the test code I am using to create the key scanner for the three ports.
// ==============
GPIO_SetBits(KP_ROW1_PORT, KP_ROW1_PIN);
for(i=0x1FF; i>0; i--);
GPIO_ResetBits(KP_ROW1_PORT, KP_ROW1_PIN);
for(i=0x1FF; i>0; i--);
GPIO_SetBits(KP_ROW2_PORT, KP_ROW2_PIN);
for(i=0x1FF; i>0; i--);
GPIO_ResetBits(KP_ROW2_PORT, KP_ROW2_PIN);
for(i=0x1FF; i>0; i--);
GPIO_SetBits(KP_ROW3_PORT, KP_ROW3_PIN);
for(i=0x1FF; i>0; i--);
GPIO_ResetBits(KP_ROW3_PORT, KP_ROW3_PIN);
for(i=0x1FF; i>0; i--);