diff --git a/Marlin/Marlin_main.cpp b/Marlin/Marlin_main.cpp
index 5dab1f40e6..0866a08dd5 100644
--- a/Marlin/Marlin_main.cpp
+++ b/Marlin/Marlin_main.cpp
@@ -5285,8 +5285,8 @@ inline void gcode_M121() { endstops.enable_globally(false); }
uint8_t bytes = code_seen('B') ? code_value_byte() : 1;
- if (i2c.addr > 0 && bytes > 0 && bytes <= 32) {
- i2c.reqbytes(bytes);
+ if (i2c.addr && bytes && bytes <= TWIBUS_BUFFER_SIZE) {
+ i2c.relay(bytes);
}
else {
SERIAL_ERROR_START;
diff --git a/Marlin/twibus.cpp b/Marlin/twibus.cpp
index ab04fa368b..bf17db3c28 100644
--- a/Marlin/twibus.cpp
+++ b/Marlin/twibus.cpp
@@ -86,32 +86,72 @@ void TWIBus::send() {
this->reset();
}
-void TWIBus::echodata(uint8_t bytes, const char prefix[], uint8_t adr) {
+// static
+void TWIBus::echoprefix(uint8_t bytes, const char prefix[], uint8_t adr) {
SERIAL_ECHO_START;
serialprintPGM(prefix);
SERIAL_ECHOPAIR(": from:", adr);
SERIAL_ECHOPAIR(" bytes:", bytes);
SERIAL_ECHOPGM (" data:");
+}
+
+// static
+void TWIBus::echodata(uint8_t bytes, const char prefix[], uint8_t adr) {
+ echoprefix(bytes, prefix, adr);
while (bytes-- && Wire.available()) SERIAL_CHAR(Wire.read());
SERIAL_EOL;
}
-void TWIBus::reqbytes(const uint8_t bytes) {
- if (!this->addr) return;
+void TWIBus::echobuffer(const char prefix[], uint8_t adr) {
+ echoprefix(this->buffer_s, prefix, adr);
+ for (uint8_t i = 0; i < this->buffer_s; i++) SERIAL_CHAR(this->buffer[i]);
+ SERIAL_EOL;
+}
+
+bool TWIBus::request(const uint8_t bytes) {
+ if (!this->addr) return false;
#if ENABLED(DEBUG_TWIBUS)
- debug(PSTR("reqbytes"), bytes);
+ debug(PSTR("request"), bytes);
#endif
// requestFrom() is a blocking function
Wire.requestFrom(this->addr, bytes);
- // Wait until all bytes arrive, or timeout
+ // Wait for all bytes to arrive
millis_t t = millis() + this->timeout;
- while (Wire.available() < bytes && PENDING(millis(), t)) { /*nada*/ }
+ while (Wire.available() < bytes)
+ if (ELAPSED(millis(), t)) {
+ #if ENABLED(DEBUG_TWIBUS)
+ SERIAL_ECHO_START;
+ SERIAL_ECHOLNPGM("i2c timeout");
+ #endif
+ return false;
+ }
- // Simply echo the data to the bus
- this->echodata(bytes, PSTR("i2c-reply"), this->addr);
+ return true;
+}
+
+void TWIBus::relay(const uint8_t bytes) {
+ #if ENABLED(DEBUG_TWIBUS)
+ debug(PSTR("relay"), bytes);
+ #endif
+
+ if (this->request(bytes))
+ echodata(bytes, PSTR("i2c-reply"), this->addr);
+}
+
+uint8_t TWIBus::capture(char *dst, const uint8_t bytes) {
+ this->reset();
+ uint8_t count = 0;
+ while (count < bytes && Wire.available())
+ dst[count++] = Wire.read();
+ return count;
+}
+
+// static
+void TWIBus::flush() {
+ while (Wire.available()) Wire.read();
}
#if I2C_SLAVE_ADDRESS > 0
@@ -120,7 +160,7 @@ void TWIBus::reqbytes(const uint8_t bytes) {
#if ENABLED(DEBUG_TWIBUS)
debug(PSTR("receive"), bytes);
#endif
- this->echodata(bytes, PSTR("i2c-receive"), 0);
+ echodata(bytes, PSTR("i2c-receive"), 0);
}
void TWIBus::reply(char str[]/*=NULL*/) {
@@ -142,6 +182,7 @@ void TWIBus::reqbytes(const uint8_t bytes) {
#if ENABLED(DEBUG_TWIBUS)
+ // static
void TWIBus::prefix(const char func[]) {
SERIAL_ECHOPGM("TWIBus::");
serialprintPGM(func);
diff --git a/Marlin/twibus.h b/Marlin/twibus.h
index 32928a8e15..d578a6d1fb 100644
--- a/Marlin/twibus.h
+++ b/Marlin/twibus.h
@@ -33,6 +33,8 @@
typedef void (*twiReceiveFunc_t)(int bytes);
typedef void (*twiRequestFunc_t)();
+#define TWIBUS_BUFFER_SIZE 32
+
/**
* TWIBUS class
*
@@ -70,7 +72,7 @@ class TWIBus {
* @brief Internal buffer
* @details A fixed buffer. TWI commands can be no longer than this.
*/
- char buffer[32];
+ char buffer[TWIBUS_BUFFER_SIZE];
public:
@@ -134,6 +136,14 @@ class TWIBus {
*/
void address(const uint8_t adr);
+ /**
+ * @brief Prefix for echo to serial
+ * @details Echo a label, length, address, and "data:"
+ *
+ * @param bytes the number of bytes to request
+ */
+ static void echoprefix(uint8_t bytes, const char prefix[], uint8_t adr);
+
/**
* @brief Echo data on the bus to serial
* @details Echo some number of bytes from the bus
@@ -144,14 +154,48 @@ class TWIBus {
static void echodata(uint8_t bytes, const char prefix[], uint8_t adr);
/**
- * @brief Request data from the slave device
- * @details Request a number of bytes from a slave device.
- * This implementation simply sends the data to serial
- * in a parser-friendly format.
+ * @brief Echo data in the buffer to serial
+ * @details Echo the entire buffer to serial
+ * to serial in a parser-friendly format.
*
* @param bytes the number of bytes to request
*/
- void reqbytes(const uint8_t bytes);
+ void echobuffer(const char prefix[], uint8_t adr);
+
+ /**
+ * @brief Request data from the slave device and wait.
+ * @details Request a number of bytes from a slave device.
+ * Wait for the data to arrive until the timeout
+ * interval expires. Return true on success.
+ *
+ * @param bytes the number of bytes to request
+ * @return status of the request: true=success, false=timeout
+ */
+ bool request(const uint8_t bytes);
+
+ /**
+ * @brief Capture data from the bus into the buffer.
+ * @details Capture data after a request has succeeded.
+ *
+ * @param bytes the number of bytes to request
+ * @return the number of bytes captured to the buffer
+ */
+ uint8_t capture(char *dst, const uint8_t bytes);
+
+ /**
+ * @brief Flush the i2c bus.
+ * @details Get all bytes on the bus and throw them away.
+ */
+ static void flush();
+
+ /**
+ * @brief Request data from the slave device, echo to serial.
+ * @details Request a number of bytes from a slave device and output
+ * the returned data to serial in a parser-friendly format.
+ *
+ * @param bytes the number of bytes to request
+ */
+ void relay(const uint8_t bytes);
#if I2C_SLAVE_ADDRESS > 0
@@ -181,6 +225,7 @@ class TWIBus {
/**
* @brief Send a reply to the bus
* @details Send the buffer and clear it.
+ * If a string is passed, write it into the buffer first.
*/
void reply(char str[]=NULL);
inline void reply(const char str[]) { this->reply((char*)str); }