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-rw-r--r--libraries/Wire/README5
-rw-r--r--libraries/Wire/Wire.cpp259
-rw-r--r--libraries/Wire/Wire.h99
-rw-r--r--libraries/Wire/rules.mk29
4 files changed, 392 insertions, 0 deletions
diff --git a/libraries/Wire/README b/libraries/Wire/README
new file mode 100644
index 0000000..353d51a
--- /dev/null
+++ b/libraries/Wire/README
@@ -0,0 +1,5 @@
+Wirish soft (bit-banged) implementation of the Wire I2C library.
+
+This implementation is synchronous, and thus supports only a subset of
+the full Wire interface. An asynchronous hardware version implemented
+with DMA is expected for Maple IDE release 0.1.0.
diff --git a/libraries/Wire/Wire.cpp b/libraries/Wire/Wire.cpp
new file mode 100644
index 0000000..736bd25
--- /dev/null
+++ b/libraries/Wire/Wire.cpp
@@ -0,0 +1,259 @@
+/******************************************************************************
+ * The MIT License
+ *
+ * Copyright (c) 2010 LeafLabs LLC.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *****************************************************************************/
+
+/**
+ * @brief Wire library, ported from Arduino. Provides a simplistic
+ * interface to i2c.
+ */
+
+#include "Wire.h"
+#include "wirish.h"
+
+/* low level conventions:
+ * - SDA/SCL idle high (expected high)
+ * - always start with i2c_delay rather than end
+ */
+uint32 i2c_delay = 1;
+
+void i2c_start(Port port) {
+ I2C_DELAY;
+ digitalWrite(port.sda,LOW);
+ I2C_DELAY;
+ digitalWrite(port.scl,LOW);
+}
+
+void i2c_stop(Port port) {
+ I2C_DELAY;
+ digitalWrite(port.scl,HIGH);
+ I2C_DELAY;
+ digitalWrite(port.sda,HIGH);
+}
+
+boolean i2c_get_ack(Port port) {
+ I2C_DELAY;
+ digitalWrite(port.scl,LOW);
+ I2C_DELAY;
+ digitalWrite(port.sda,HIGH);
+ I2C_DELAY;
+ digitalWrite(port.scl,HIGH);
+ I2C_DELAY;
+
+ if (!digitalRead(port.sda)) {
+ I2C_DELAY;
+ digitalWrite(port.scl,LOW);
+ return true;
+ } else {
+ I2C_DELAY;
+ digitalWrite(port.scl,LOW);
+ return false;
+ }
+}
+
+void i2c_send_ack(Port port) {
+ I2C_DELAY;
+ digitalWrite(port.sda,LOW);
+ I2C_DELAY;
+ digitalWrite(port.scl,HIGH);
+ I2C_DELAY;
+ digitalWrite(port.scl,LOW);
+}
+
+void i2c_send_nack(Port port) {
+ I2C_DELAY;
+ digitalWrite(port.sda,HIGH);
+ I2C_DELAY;
+ digitalWrite(port.scl,HIGH);
+}
+
+uint8 i2c_shift_in(Port port) {
+ uint8 data = 0;
+
+ int i;
+ for (i=0;i<8;i++) {
+ I2C_DELAY;
+ digitalWrite(port.scl,HIGH);
+ I2C_DELAY;
+ data += digitalRead(port.sda) << (7-i);
+ I2C_DELAY;
+ digitalWrite(port.scl,LOW);
+ }
+
+ return data;
+}
+
+void i2c_shift_out(Port port, uint8 val) {
+ int i;
+ for (i=0;i<8;i++) {
+ I2C_DELAY;
+ digitalWrite(port.sda, !!(val & (1 << (7 - i))));
+ I2C_DELAY;
+ digitalWrite(port.scl, HIGH);
+ I2C_DELAY;
+ digitalWrite(port.scl, LOW);
+ }
+}
+
+TwoWire::TwoWire() {
+ i2c_delay = 0;
+ rx_buf_idx = 0;
+ rx_buf_len = 0;
+ tx_addr = 0;
+ tx_buf_idx = 0;
+ tx_buf_overflow = false;
+}
+
+/*
+ * Sets pins SDA and SCL to OUPTUT_OPEN_DRAIN, joining I2C bus as
+ * master. If you want them to be some other pins, use begin(uint8,
+ * uint8);
+ */
+void TwoWire::begin() {
+ begin(SDA, SCL);
+}
+
+/*
+ * Joins I2C bus as master on given SDA and SCL pins.
+ */
+void TwoWire::begin(uint8 sda, uint8 scl) {
+ port.sda = sda;
+ port.scl = scl;
+ pinMode(scl, OUTPUT_OPEN_DRAIN);
+ pinMode(sda, OUTPUT_OPEN_DRAIN);
+ digitalWrite(scl, HIGH);
+ digitalWrite(sda, HIGH);
+}
+
+void TwoWire::beginTransmission(uint8 slave_address) {
+ tx_addr = slave_address;
+ tx_buf_idx = 0;
+ tx_buf_overflow = false;
+ rx_buf_idx = 0;
+ rx_buf_len = 0;
+}
+
+void TwoWire::beginTransmission(int slave_address) {
+ beginTransmission((uint8)slave_address);
+}
+
+uint8 TwoWire::endTransmission(void) {
+ if (tx_buf_overflow) return EDATA;
+
+ i2c_start(port);
+
+ i2c_shift_out(port, (tx_addr << 1) | I2C_WRITE);
+ if (!i2c_get_ack(port)) return ENACKADDR;
+
+ // shift out the address we're transmitting to
+ for (uint8 i = 0; i < tx_buf_idx; i++) {
+ uint8 ret = writeOneByte(tx_buf[i]);
+ if (ret) return ret; // SUCCESS is 0
+ }
+
+ i2c_stop(port);
+
+ tx_buf_idx = 0;
+ tx_buf_overflow = false;
+ return SUCCESS;
+}
+
+uint8 TwoWire::requestFrom(uint8 address, int num_bytes) {
+ if (num_bytes > WIRE_BUFSIZ) num_bytes = WIRE_BUFSIZ;
+
+ rx_buf_idx = 0;
+ rx_buf_len = 0;
+ while (rx_buf_len < num_bytes) {
+ if(!readOneByte(address, rx_buf + rx_buf_len)) rx_buf_len++;
+ else break;
+ }
+ return rx_buf_len;
+}
+
+uint8 TwoWire::requestFrom(int address, int numBytes) {
+ return TwoWire::requestFrom((uint8)address, (uint8) numBytes);
+}
+
+void TwoWire::send(uint8 value) {
+ if (tx_buf_idx == WIRE_BUFSIZ) {
+ tx_buf_overflow = true;
+ return;
+ }
+
+ tx_buf[tx_buf_idx++] = value;
+}
+
+void TwoWire::send(uint8* buf, int len) {
+ for (uint8 i = 0; i < len; i++) send(buf[i]);
+}
+
+void TwoWire::send(int value) {
+ send((uint8)value);
+}
+
+void TwoWire::send(int* buf, int len) {
+ send((uint8*)buf, (uint8)len);
+}
+
+void TwoWire::send(char* buf) {
+ uint8 *ptr = (uint8*)buf;
+ while(*ptr) {
+ send(*ptr);
+ ptr++;
+ }
+}
+
+uint8 TwoWire::available() {
+ return rx_buf_len - rx_buf_idx;
+}
+
+uint8 TwoWire::receive() {
+ if (rx_buf_idx == rx_buf_len) return 0;
+ return rx_buf[rx_buf_idx++];
+}
+
+// private methods
+
+uint8 TwoWire::writeOneByte(uint8 byte) {
+ i2c_shift_out(port, byte);
+ if (!i2c_get_ack(port)) return ENACKTRNS;
+
+ return SUCCESS;
+}
+
+uint8 TwoWire::readOneByte(uint8 address, uint8 *byte) {
+ i2c_start(port);
+
+ i2c_shift_out(port, (address << 1) | I2C_READ);
+ if (!i2c_get_ack(port)) return ENACKADDR;
+
+ *byte = i2c_shift_in(port);
+
+ i2c_send_nack(port);
+ i2c_stop(port);
+
+ return SUCCESS; // no real way of knowing, but be optimistic!
+}
+
+// Declare the instance that the users of the library can use
+TwoWire Wire;
+
diff --git a/libraries/Wire/Wire.h b/libraries/Wire/Wire.h
new file mode 100644
index 0000000..62e37bd
--- /dev/null
+++ b/libraries/Wire/Wire.h
@@ -0,0 +1,99 @@
+/* *****************************************************************************
+ * The MIT License
+ *
+ * Copyright (c) 2010 LeafLabs LLC.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ * ****************************************************************************/
+
+/**
+ * @brief Wire library, ported from Arduino. Provides a lean
+ * interface to I2C (two-wire) communication.
+ */
+
+#include "wirish.h"
+
+#ifndef _WIRE_H_
+#define _WIRE_H_
+
+typedef struct {
+ uint8 scl;
+ uint8 sda;
+} Port;
+
+/* You must update the online docs if you change this value. */
+#define WIRE_BUFSIZ 32
+
+/* return codes from endTransmission() */
+#define SUCCESS 0 /* transmission was successful */
+#define EDATA 1 /* too much data */
+#define ENACKADDR 2 /* received nack on transmit of address */
+#define ENACKTRNS 3 /* received nack on transmit of data */
+#define EOTHER 4 /* other error */
+
+#define SDA 20
+#define SCL 21
+
+#define I2C_WRITE 0
+#define I2C_READ 1
+
+#define I2C_DELAY do{for(int i=0;i<50;i++) {asm volatile("nop");}}while(0)
+
+class TwoWire {
+ private:
+ uint8 rx_buf[WIRE_BUFSIZ]; /* receive buffer */
+ uint8 rx_buf_idx; /* first unread idx in rx_buf */
+ uint8 rx_buf_len; /* number of bytes read */
+
+ uint8 tx_addr; /* address transmitting to */
+ uint8 tx_buf[WIRE_BUFSIZ]; /* transmit buffer */
+ uint8 tx_buf_idx; /* next idx available in tx_buf, -1 overflow */
+ boolean tx_buf_overflow;
+ Port port;
+ uint8 writeOneByte(uint8);
+ uint8 readOneByte(uint8, uint8*);
+ public:
+ TwoWire();
+ void begin();
+ void begin(uint8, uint8);
+ void beginTransmission(uint8);
+ void beginTransmission(int);
+ uint8 endTransmission(void);
+ uint8 requestFrom(uint8, int);
+ uint8 requestFrom(int, int);
+ void send(uint8);
+ void send(uint8*, int);
+ void send(int);
+ void send(int*, int);
+ void send(char*);
+ uint8 available();
+ uint8 receive();
+};
+
+void i2c_start(Port port);
+void i2c_stop(Port port);
+boolean i2c_get_ack(Port port);
+void i2c_send_ack(Port port);
+void i2c_send_nack(Port port);
+uint8 i2c_shift_in(Port port);
+void i2c_shift_out(Port port, uint8 val);
+
+extern TwoWire Wire;
+
+#endif // _WIRE_H_
diff --git a/libraries/Wire/rules.mk b/libraries/Wire/rules.mk
new file mode 100644
index 0000000..71f5e75
--- /dev/null
+++ b/libraries/Wire/rules.mk
@@ -0,0 +1,29 @@
+# Standard things
+sp := $(sp).x
+dirstack_$(sp) := $(d)
+d := $(dir)
+BUILDDIRS += $(BUILD_PATH)/$(d)
+
+# Local flags
+CFLAGS_$(d) := $(WIRISH_INCLUDES) $(LIBMAPLE_INCLUDES)
+
+# Local rules and targets
+cSRCS_$(d) :=
+
+cppSRCS_$(d) := Wire.cpp
+
+cFILES_$(d) := $(cSRCS_$(d):%=$(d)/%)
+cppFILES_$(d) := $(cppSRCS_$(d):%=$(d)/%)
+
+OBJS_$(d) := $(cFILES_$(d):%.c=$(BUILD_PATH)/%.o) \
+ $(cppFILES_$(d):%.cpp=$(BUILD_PATH)/%.o)
+DEPS_$(d) := $(OBJS_$(d):%.o=%.d)
+
+$(OBJS_$(d)): TGT_CFLAGS := $(CFLAGS_$(d))
+
+TGT_BIN += $(OBJS_$(d))
+
+# Standard things
+-include $(DEPS_$(d))
+d := $(dirstack_$(sp))
+sp := $(basename $(sp)) \ No newline at end of file
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-21 21:56:41 +0000