|
|
@@ -15,19 +15,203 @@
|
|
|
*/
|
|
|
|
|
|
#include "twi2c.h"
|
|
|
+#include <string.h>
|
|
|
+#include <hal.h>
|
|
|
+#include "hal_i2cslave.h"
|
|
|
+#include "chprintf.h"
|
|
|
+#include "memstreams.h"
|
|
|
+#include "printf.h"
|
|
|
|
|
|
#ifndef I2C_DRIVER
|
|
|
- #define I2C_DRIVER &I2CD1
|
|
|
+ #define I2C_DRIVER I2CD1
|
|
|
#endif
|
|
|
|
|
|
-static const I2CConfig i2cconfig = {
|
|
|
+/**
|
|
|
+ * I2C slave test routine.
|
|
|
+ *
|
|
|
+ * To use: Add file to a project, call startComms() with the address of a serial stream
|
|
|
+ *
|
|
|
+ * There are two different responses:
|
|
|
+ * a) A read-only transaction - returns the "Initial Reply" message
|
|
|
+ * b) A write then read transaction - calls a message processor and returns the generated reply.
|
|
|
+ * Stretches clock until reply available.
|
|
|
+ */
|
|
|
+
|
|
|
+
|
|
|
+#define slaveI2Caddress 0x30 /* Address in our terms - halved by later code */
|
|
|
+//#define myOtherI2Caddress 0x19
|
|
|
+
|
|
|
+I2CSlaveMsgCB twi2c_slave_message_process, catchError, clearAfterSend;
|
|
|
+
|
|
|
+static const I2CConfig slaveI2Cconfig = {
|
|
|
STM32_TIMINGR_PRESC(15U) |
|
|
|
STM32_TIMINGR_SCLDEL(4U) | STM32_TIMINGR_SDADEL(2U) |
|
|
|
STM32_TIMINGR_SCLH(15U) | STM32_TIMINGR_SCLL(21U),
|
|
|
0,
|
|
|
- 0
|
|
|
+ 0,
|
|
|
+ NULL
|
|
|
};
|
|
|
|
|
|
-void twi2c_init(void) {
|
|
|
- i2cStart(I2C_DRIVER, &i2cconfig);
|
|
|
-}
|
|
|
+char initialReplyBody[50] = "Initial reply"; // 'Status' response if read without preceding write
|
|
|
+
|
|
|
+
|
|
|
+uint32_t messageCounter = 0; /* Counts number of messages received to return as part of response */
|
|
|
+
|
|
|
+uint8_t rxBody[240]; /* stores last message master sent us (intentionally a few bytes smaller than txBody) */
|
|
|
+uint8_t txBody[256]; /* Return message buffer for computed replies */
|
|
|
+
|
|
|
+BaseSequentialStream *chp = NULL; // Used for serial logging
|
|
|
+
|
|
|
+// Handler when something sent to us
|
|
|
+const I2CSlaveMsg echoRx =
|
|
|
+{
|
|
|
+ sizeof(rxBody), /* max sizeof received msg body */
|
|
|
+ rxBody, /* body of received msg */
|
|
|
+ NULL, /* do nothing on address match */
|
|
|
+ twi2c_slave_message_process, /* Routine to process received messages */
|
|
|
+ catchError /* Error hook */
|
|
|
+};
|
|
|
+
|
|
|
+
|
|
|
+// 'Empty' reply when nothing to say, and no message received. In RAM, to allow update
|
|
|
+I2CSlaveMsg initialReply =
|
|
|
+{
|
|
|
+ sizeof(initialReplyBody), /* trailing zero byte will be repeated as needed */
|
|
|
+ (uint8_t *)initialReplyBody,
|
|
|
+ NULL, /* do nothing on address match */
|
|
|
+ NULL, /* do nothing after reply sent */
|
|
|
+ catchError /* Error hook */
|
|
|
+};
|
|
|
+
|
|
|
+
|
|
|
+// Response to received messages
|
|
|
+I2CSlaveMsg echoReply = { /* this is in RAM so size may be updated */
|
|
|
+ 0, /* filled in with the length of the message to send */
|
|
|
+ txBody, /* Response message */
|
|
|
+ NULL, /* do nothing special on address match */
|
|
|
+ clearAfterSend, /* Clear receive buffer once replied */
|
|
|
+ catchError /* Error hook */
|
|
|
+};
|
|
|
+
|
|
|
+
|
|
|
+/**
|
|
|
+ * Track I2C errors
|
|
|
+ */
|
|
|
+uint8_t gotI2cError = 0;
|
|
|
+uint32_t lastI2cErrorFlags = 0;
|
|
|
+
|
|
|
+// Called from ISR to log error
|
|
|
+void noteI2cError(uint32_t flags)
|
|
|
+{
|
|
|
+ lastI2cErrorFlags = flags;
|
|
|
+ gotI2cError = 1;
|
|
|
+}
|
|
|
+
|
|
|
+
|
|
|
+
|
|
|
+/**
|
|
|
+ * Generic error handler
|
|
|
+ *
|
|
|
+ * Called in interrupt context, so need to watch what we do
|
|
|
+ */
|
|
|
+void catchError(I2CDriver *i2cp)
|
|
|
+{
|
|
|
+ noteI2cError(i2cp->errors);
|
|
|
+}
|
|
|
+
|
|
|
+
|
|
|
+
|
|
|
+const char hexString[16] = "0123456789abcdef";
|
|
|
+
|
|
|
+
|
|
|
+/**
|
|
|
+ * Message processor - looks at received message, determines reply as quickly as possible
|
|
|
+ *
|
|
|
+ * Responds with the value of the messageCounter (in hex), followed by the received message in [..]
|
|
|
+ *
|
|
|
+ * Note: Called in interrupt context, so need to be quick!
|
|
|
+ */
|
|
|
+void twi2c_slave_message_process(I2CDriver *i2cp) {
|
|
|
+ uint8_t i;
|
|
|
+ uint8_t *txPtr = txBody + 8;
|
|
|
+ uint8_t txLen;
|
|
|
+ uint32_t curCount;
|
|
|
+
|
|
|
+ size_t len = i2cSlaveBytes(i2cp); // Number of bytes received
|
|
|
+ if (len >= sizeof(rxBody))
|
|
|
+ len = sizeof(rxBody)-1;
|
|
|
+ rxBody[len]=0; // String termination sometimes useful
|
|
|
+
|
|
|
+ /* A real-world application would read and decode the message in rxBody, then generate an appropriate reply in txBody */
|
|
|
+
|
|
|
+ curCount = ++messageCounter;
|
|
|
+ txLen = len + 11; // Add in the overhead
|
|
|
+
|
|
|
+ for (i = 0; i < 8; i++)
|
|
|
+ {
|
|
|
+ *--txPtr = hexString[curCount & 0xf];
|
|
|
+ curCount = curCount >> 4;
|
|
|
+ }
|
|
|
+
|
|
|
+ txPtr = txBody + 8;
|
|
|
+ *txPtr++ = ' ';
|
|
|
+ *txPtr++ = '[';
|
|
|
+ memcpy(txPtr, rxBody, len); // Echo received message
|
|
|
+ txPtr += len;
|
|
|
+ *txPtr++ = ']';
|
|
|
+ *txPtr = '\0';
|
|
|
+
|
|
|
+ /** Message ready to go here */
|
|
|
+ echoReply.size = txLen;
|
|
|
+ i2cSlaveReplyI(i2cp, &echoReply);
|
|
|
+}
|
|
|
+
|
|
|
+
|
|
|
+/**
|
|
|
+ * Callback after sending of response complete - restores default reply in case polled
|
|
|
+ */
|
|
|
+void clearAfterSend(I2CDriver *i2cp)
|
|
|
+{
|
|
|
+ echoReply.size = 0; // Clear receive message
|
|
|
+ i2cSlaveReplyI(i2cp, &initialReply);
|
|
|
+}
|
|
|
+
|
|
|
+
|
|
|
+/**
|
|
|
+ * Start the I2C Slave port to accept comms from master CPU
|
|
|
+ *
|
|
|
+ * We then go into a loop checking for errors, and never return
|
|
|
+ */
|
|
|
+
|
|
|
+void twi2c_slave_init(void) {
|
|
|
+
|
|
|
+ palSetGroupMode(GPIOB,8,9, PAL_MODE_INPUT); // Try releasing special pins for a short time
|
|
|
+ chThdSleepMilliseconds(10);
|
|
|
+
|
|
|
+ /* I2C1 SCL on PF1, SDA on PF0 */
|
|
|
+ palSetPadMode(GPIOB, 9, PAL_MODE_ALTERNATE(4) | PAL_STM32_OTYPE_OPENDRAIN | PAL_STM32_PUPDR_PULLUP);
|
|
|
+ palSetPadMode(GPIOB, 8, PAL_MODE_ALTERNATE(4) | PAL_STM32_OTYPE_OPENDRAIN | PAL_STM32_PUPDR_PULLUP);
|
|
|
+
|
|
|
+
|
|
|
+ i2cStart(&I2C_DRIVER, &slaveI2Cconfig);
|
|
|
+#if HAL_USE_I2C_SLAVE
|
|
|
+ I2C_DRIVER.slaveTimeout = MS2ST(100); // Time for complete message
|
|
|
+#endif
|
|
|
+
|
|
|
+ i2cSlaveConfigure(&I2C_DRIVER, &echoRx, &initialReply);
|
|
|
+
|
|
|
+ // Enable match address after everything else set up
|
|
|
+ i2cMatchAddress(&I2C_DRIVER, slaveI2Caddress/2);
|
|
|
+// i2cMatchAddress(&I2C_DRIVER, myOtherI2Caddress/2);
|
|
|
+// i2cMatchAddress(&I2C_DRIVER, 0); /* "all call" */
|
|
|
+
|
|
|
+ printf("Slave I2C started\n\r");
|
|
|
+
|
|
|
+}
|
|
|
+
|
|
|
+void twi2c_slave_task(void) {
|
|
|
+ if (gotI2cError) {
|
|
|
+ gotI2cError = 0;
|
|
|
+ printf("I2cError: %04x\r\n", lastI2cErrorFlags);
|
|
|
+ }
|
|
|
+}
|
Jack Humbert