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AnswerRe: Adding two matrix objects and assigning the result to third object using overloaded operators ? Pin
Richard MacCutchan24-Mar-18 21:13
mveRichard MacCutchan24-Mar-18 21:13 
GeneralRe: Adding two matrix objects and assigning the result to third object using overloaded operators ? Pin
Tarun Jha25-Mar-18 5:08
Tarun Jha25-Mar-18 5:08 
GeneralRe: Adding two matrix objects and assigning the result to third object using overloaded operators ? Pin
Richard MacCutchan25-Mar-18 5:32
mveRichard MacCutchan25-Mar-18 5:32 
GeneralRe: Adding two matrix objects and assigning the result to third object using overloaded operators ? Pin
Tarun Jha25-Mar-18 6:37
Tarun Jha25-Mar-18 6:37 
GeneralRe: Adding two matrix objects and assigning the result to third object using overloaded operators ? Pin
Richard MacCutchan25-Mar-18 7:16
mveRichard MacCutchan25-Mar-18 7:16 
GeneralRe: Adding two matrix objects and assigning the result to third object using overloaded operators ? Pin
Tarun Jha25-Mar-18 8:06
Tarun Jha25-Mar-18 8:06 
QuestionLinux C++ implementation of ioctl SOLVED Pin
Vaclav_23-Mar-18 8:50
Vaclav_23-Mar-18 8:50 
AnswerRe: Linux C++ implementation of ioctl Pin
Jochen Arndt24-Mar-18 23:39
professionalJochen Arndt24-Mar-18 23:39 
You have two options:

  1. Use the existing I2C support on the Raspberry Pi with the I2C GPIO pins
  2. Implement your own I2C support on general use GPIO pins

The I2C speed is defined by the master by generating the clock. A device might use "clock stretching" to slow down (Clock, Stretching, Arbitration - I2C Bus[^]).

So implementations are not time critical. They can use a predefined (max.) clock and have not to care about being slowed down by other tasks on the system.

I have implemented I2C in assembler on micro controllers. Implementing it in C is not a problem but be aware that it might be a frustrating tasks because it can't be simply debugged. I highly recommend to use a logic analyser or at least a storage oscilloscope to check the signals on the bus.

Quote:
all of the sample codes I have read so far are "limited" to open ioctl file and "write " to I2C slave address.
With device drivers use i2c_transfer(). Have a look at the source of any Linux driver for a I2C device like rtc-pcf8563.c
[^].

When using ioctl() on the I2C device just use read():
C++
int fd = open("/dev/i2c-1", O_RDWR);
// Use I2C_SLAVE_FORCE if the device is in use (e.g. when a driver is installed)
ioctl(fd, I2C_SLAVE, addr);
read(fd, buffer, length);
Or use ioctl(I2C_RDWR) or ioctl(I2C_SMBUS) for reading which both does not require the I2C_SLAVE[_FORCE]. In any case check first if the used ioctl() call is supported.
AnswerRe: Linux C++ implementation of ioctl Pin
leon de boer26-Mar-18 16:53
leon de boer26-Mar-18 16:53 
GeneralRe: Linux C++ implementation of ioctl Pin
Vaclav_4-Apr-18 5:08
Vaclav_4-Apr-18 5:08 
QuestionVS2017: Cannot debug Dll's Pin
indrekm23-Mar-18 1:13
indrekm23-Mar-18 1:13 
SuggestionRe: VS2017: Cannot debug Dll's Pin
Richard MacCutchan23-Mar-18 1:21
mveRichard MacCutchan23-Mar-18 1:21 
SuggestionRe: VS2017: Cannot debug Dll's Pin
Jochen Arndt23-Mar-18 1:25
professionalJochen Arndt23-Mar-18 1:25 
AnswerRe: VS2017: Cannot debug Dll's Pin
Randor 23-Mar-18 8:09
professional Randor 23-Mar-18 8:09 
QuestionSelect and Pick lines in OpenGL Pin
Gopi Nath22-Mar-18 19:40
Gopi Nath22-Mar-18 19:40 
AnswerRe: Select and Pick lines in OpenGL Pin
leon de boer22-Mar-18 20:30
leon de boer22-Mar-18 20:30 
GeneralRe: Select and Pick lines in OpenGL Pin
Gopi Nath22-Mar-18 21:08
Gopi Nath22-Mar-18 21:08 
GeneralRe: Select and Pick lines in OpenGL Pin
Gopi Nath24-Jul-18 21:17
Gopi Nath24-Jul-18 21:17 
QuestionNotifiation Messages for CSpinButtonCtrl in MFC Pin
Sampath57922-Mar-18 3:46
Sampath57922-Mar-18 3:46 
AnswerRe: Notifiation Messages for CSpinButtonCtrl in MFC Pin
Jochen Arndt22-Mar-18 4:32
professionalJochen Arndt22-Mar-18 4:32 
GeneralRe: Notifiation Messages for CSpinButtonCtrl in MFC Pin
Sampath57922-Mar-18 7:31
Sampath57922-Mar-18 7:31 
GeneralRe: Notifiation Messages for CSpinButtonCtrl in MFC Pin
Victor Nijegorodov22-Mar-18 8:37
Victor Nijegorodov22-Mar-18 8:37 
GeneralRe: Notifiation Messages for CSpinButtonCtrl in MFC Pin
Sampath57922-Mar-18 17:10
Sampath57922-Mar-18 17:10 
GeneralRe: Notifiation Messages for CSpinButtonCtrl in MFC Pin
Victor Nijegorodov22-Mar-18 21:45
Victor Nijegorodov22-Mar-18 21:45 
GeneralRe: Notifiation Messages for CSpinButtonCtrl in MFC Pin
Jochen Arndt22-Mar-18 9:46
professionalJochen Arndt22-Mar-18 9:46 

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