GPIO over CPLD

Each of the 4 GPIO ports contains 8 ouput and 8 input pins. The ports are not as fast as the integrated GPIO ports of the microcontroller.

Please make sure the CT Board is in the correct mode.
Supported mode: 1

 {{ctboard_gpio_input_reg.svg}} \\ \\

The registers are read / write.

The code snippets below show how to use the GPIO.

#include "reg_ctboard.h"
 
uint8_t data_byte = CT_GPIO->IN.BYTE.P1;              /* Read byte from P1. */
uint16_t data_hword = CT_GPIO->IN.HWORD.P2_1;         /* Read half word from P1 and P2. */
uint32_t data_word = CT_GPIO->IN.WORD;                /* Read word from all ports (P1..4). */
 
CT_GPIO->OUT.BYTE.P3 = (uint8_t) data_byte;           /* Write byte of data to P3. */
CT_GPIO->OUT.HWORD.P4_3 = (uint16_t) data_halfword;   /* Write halfword of data to P3..4 */
CT_GPIO->OUT.WORD = (uint32_t) data_word;             /* Write word of data to all ports (P1..4). */

.equ ADDR_GPIO_IN,   0x60000410
.equ ADDR_GPIO_OUT,  0x60000400
 
        ldr     r0,  =ADDR_GPIO_IN
        ldrb    r1,  [r0, #0]                 // Read byte from P1.
        ldrw    r1,  [r0, #0]                 // Read half word from P1 and P2.
        ldr     r1,  [r0, #0]                 // Read word from all ports (P1..4).
 
        ldr     r0,  =ADDR_GPIO_OUT
        strb    r1,  [r0, #2]                 // Write byte of data to P3.
        strh    r1,  [r0, #2]                 // Write halfword of data to P3..4.
        str     r1,  [r0, #0]                 // Write word of data to all ports (P1..4).