Chris Heald
/
KL25Z_I2C_busreset
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KL25Z_I2C_busreset
by 
Frank Vannieuwkerke
Revision 0:e9beb537cf77, committed 2014-02-19
- Comitter:
- frankvnk
- Date:
- Wed Feb 19 19:18:49 2014 +0000
- Child:
- 1:fe493f707844
- Commit message:
- Initial release
Changed in this revision
| I2C_busreset.cpp | Show annotated file Show diff for this revision Revisions of this file |
| I2C_busreset.h | Show annotated file Show diff for this revision Revisions of this file |
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/I2C_busreset.cpp Wed Feb 19 19:18:49 2014 +0000
@@ -0,0 +1,61 @@
+/**************************************************************************************************
+ ***** *****
+ ***** Name: KL25Z I2C_busreset.cpp *****
+ ***** Date: 24/11/2013 *****
+ ***** Auth: Frank Vannieuwkerke *****
+ ***** Func: library for unblocking I2C bus on KL25Z board *****
+ ***** Info: MPL3115A2-AN4481 *****
+ **************************************************************************************************/
+
+#include "I2C_busreset.h"
+
+void I2C_busreset(void)
+{
+ if((PORTE->PCR[1] & PORT_PCR_MUX(6)) && (PORTE->PCR[0] & PORT_PCR_MUX(6)))
+ {
+ I2C1->C1 &= 0x7f; // Disable I2C1 bus
+ PORTE->PCR[1] = PORT_PCR_MUX(1); // PTE1 Alt1 (pin)
+ PORTE->PCR[0] = PORT_PCR_MUX(1); // PTE0 Alt1 (pin)
+ if((PTE->PDIR & 0x3) != 3) // When PTE0 / PTE1 are not 1 : I2C1 bus lock-up
+ {
+ PTE->PDDR |= 0x2; // Set PTE1 as a GPIO output so we can bit bang it
+ PTE->PDOR |= 0x2; // Set PTE1 (SCL) pin high;
+ wait_ms(1);
+ while(!(PTE->PDIR & 0x1)) // bit bang SCL until the offending device releases the bus
+ {
+ PTE->PDOR &= 0xfffffffd; // Set PTE1 (SCL) pin low;
+ wait_ms(1);
+ PTE->PDOR |= 0x2; // Set PTE1 (SCL) pin high;
+ wait_ms(1);
+ }
+ }
+ // Reinstate I2C1 bus pins
+ PORTE->PCR[1] = PORT_PCR_MUX(6); // PTE1 Alt6 (SCL)
+ PORTE->PCR[0] = PORT_PCR_MUX(6); // PTE0 Alt6 (SDA)
+ I2C1->C1 |= 0x80; // Enable I2C1 bus
+ }
+
+ if((PORTE->PCR[24] & PORT_PCR_MUX(5)) && (PORTE->PCR[25] & PORT_PCR_MUX(5)))
+ {
+ I2C0->C1 &= 0x7f; // Disable I2C0 bus
+ PORTE->PCR[24] = PORT_PCR_MUX(1); // PTE24 Alt1 (pin)
+ PORTE->PCR[25] = PORT_PCR_MUX(1); // PTE25 Alt1 (pin)
+ if((PTE->PDIR & 0x03000000) != 0x03000000) // When PTE24 / PTE25 are not 1 : I2C0 bus lock-up
+ {
+ PTE->PDDR |= 0x01000000; // Set PTE24 as a GPIO output so we can bit bang it
+ PTE->PDOR |= 0x01000000; // Set PTE24 (SCL) pin high;
+ wait_ms(1);
+ while(!(PTE->PDIR & 0x1)) // bit bang SCL until the offending device releases the bus
+ {
+ PTE->PDOR &= 0xfeffffff; // Set PTE24 (SCL) pin low;
+ wait_ms(1);
+ PTE->PDOR |= 0x01000000; // Set PTE24 (SCL) pin high;
+ wait_ms(1);
+ }
+ }
+ // Reinstate I2C0 bus pins
+ PORTE->PCR[24] = PORT_PCR_MUX(5); // PTE24 Alt6 (SCL)
+ PORTE->PCR[25] = PORT_PCR_MUX(5); // PTE25 Alt6 (SDA)
+ I2C0->C1 |= 0x80; // Enable I2C0 bus
+ }
+}
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/I2C_busreset.h Wed Feb 19 19:18:49 2014 +0000 @@ -0,0 +1,17 @@ +/************************************************************************************************** + ***** ***** + ***** Name: KL25Z I2C_busreset.h ***** + ***** Date: 24/11/2013 ***** + ***** Auth: Frank Vannieuwkerke ***** + ***** Func: library for unblocking I2C bus on KL25Z board ***** + ***** Info: MPL3115A2-AN4481 ***** + **************************************************************************************************/ + +#include "mbed.h" + +#ifndef KL25Z_I2C_RES_H +#define KL25Z_I2C_RES_H + +void I2C_busreset(void); + +#endif