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-rw-r--r--src/arch/msp430fr5969lp/arch.cc7
-rw-r--r--src/arch/msp430fr5969lp/driver/i2c.cc2
-rw-r--r--src/driver/soft_i2c.cc51
3 files changed, 40 insertions, 20 deletions
diff --git a/src/arch/msp430fr5969lp/arch.cc b/src/arch/msp430fr5969lp/arch.cc
index 9ea49b7..ddb84a4 100644
--- a/src/arch/msp430fr5969lp/arch.cc
+++ b/src/arch/msp430fr5969lp/arch.cc
@@ -72,6 +72,13 @@ extern void loop();
volatile char run_loop = 0;
#endif
+void Arch::delay_us(unsigned char const us)
+{
+ for (int i = 0; i < us/10; i++) {
+ __delay_cycles(160);
+ }
+}
+
void Arch::idle_loop(void)
{
while (1) {
diff --git a/src/arch/msp430fr5969lp/driver/i2c.cc b/src/arch/msp430fr5969lp/driver/i2c.cc
index fffc28c..55f8591 100644
--- a/src/arch/msp430fr5969lp/driver/i2c.cc
+++ b/src/arch/msp430fr5969lp/driver/i2c.cc
@@ -16,7 +16,7 @@ signed char I2C::setup()
UCB0CTL1 &= ~UCSWRST;
UCB0I2CSA = 0;
- __delay_cycles(1600);
+ arch.delay_us(100);
if (UCB0STAT & UCBBUSY)
return -1;
diff --git a/src/driver/soft_i2c.cc b/src/driver/soft_i2c.cc
index 94ab261..e7b8548 100644
--- a/src/driver/soft_i2c.cc
+++ b/src/driver/soft_i2c.cc
@@ -1,32 +1,45 @@
#include "driver/soft_i2c.h"
#include "driver/gpio.h"
+#include "arch.h"
+
+#ifdef SOFTI2C_PULLUP
+#define SDA_HIGH gpio.input(sda, 1)
+#define SDA_LOW gpio.output(sda, 0)
+#define SCL_HIGH gpio.input(scl, 1)
+#define SCL_LOW gpio.output(scl, 0)
+#else
+#define SDA_HIGH gpio.input(sda)
+#define SDA_LOW gpio.output(sda)
+#define SCL_HIGH gpio.input(scl)
+#define SCL_LOW gpio.output(scl)
+#endif
signed char SoftI2C::setup()
{
- gpio.write(sda, 0);
- gpio.write(scl, 0);
+ SDA_HIGH;
+ SCL_HIGH;
return 0;
}
void SoftI2C::start()
{
- gpio.input(sda);
- gpio.input(scl);
+ SDA_HIGH;
+ SCL_HIGH;
//
- gpio.output(sda);
+ SDA_LOW;
//
- gpio.output(scl);
+ SCL_LOW;
}
void SoftI2C::stop()
{
- gpio.output(scl);
+ SCL_LOW;
//
- gpio.output(sda);
+ SDA_LOW;
//
- gpio.input(scl);
+ SCL_HIGH;
//
- gpio.input(sda);
+ SDA_HIGH;
}
bool SoftI2C::tx(unsigned char byte)
@@ -34,20 +47,20 @@ bool SoftI2C::tx(unsigned char byte)
unsigned char got_ack = 0;
for (unsigned char i = 0; i <= 8; i++) {
if ((byte & 0x80) || (i == 8)) {
- gpio.input(sda);
+ SDA_HIGH;
} else {
- gpio.output(sda);
+ SDA_LOW;
}
byte <<= 1;
//
- gpio.input(scl);
+ SCL_HIGH;
//
if (i == 8) {
if (!gpio.read(sda)) {
got_ack = 1;
}
}
- gpio.output(scl);
+ SCL_LOW;
//
}
return got_ack;
@@ -56,21 +69,21 @@ bool SoftI2C::tx(unsigned char byte)
unsigned char SoftI2C::rx(bool send_ack)
{
unsigned char byte = 0;
- gpio.input(sda);
+ SDA_HIGH;
for (unsigned char i = 0; i <= 8; i++) {
//
- gpio.input(scl);
+ SCL_HIGH;
//
if ((i < 8) && gpio.read(sda)) {
byte |= 1 << (7 - i);
}
//
- gpio.output(scl);
+ SCL_LOW;
//
if ((i == 7) && send_ack) {
- gpio.output(sda);
+ SDA_LOW;
} else if ((i == 8) && send_ack) {
- gpio.input(sda);
+ SDA_HIGH;
}
}
return byte;