Files
lib_xua/tests/i2s_loopback/xk_216_mc/gpio_access.c
Larry Snizek 79c05afdbe Release checks
2018-02-09 13:05:46 +00:00

42 lines
903 B
C

// Copyright (c) 2016-2018, XMOS Ltd, All rights reserved
#ifdef HARDWARE
#include <xs1.h>
#include "gpio_access.h"
void p_gpio_lock()
{
}
void p_gpio_unlock()
{
}
unsigned p_gpio_peek()
{
unsigned portId, x;
asm("ldw %0, dp[p_gpio]":"=r"(portId));
asm volatile("peek %0, res[%1]":"=r"(x):"r"(portId));
return x;
}
void p_gpio_out(unsigned x)
{
unsigned portId;
asm("ldw %0, dp[p_gpio]":"=r"(portId));
asm volatile("out res[%0], %1"::"r"(portId),"r"(x));
}
void set_gpio(unsigned bit, unsigned value)
{
unsigned port_shadow;
port_shadow = p_gpio_peek(); // Read port pin value
if (value == 0) port_shadow &= ~bit; // If writing a 0, generate mask and AND with current val
else port_shadow |= bit; // Else use mask and OR to set bit
p_gpio_out(port_shadow); // Write back to port. Will make port an output if not already
}
#endif