| Author |
Topic |
|
|
tscott
4 Posts |
 Posted - 29 Feb 2008 : 17:36:24
|
Is there some way to avoid polling for data on the I2C bus? I'd like to get an event or use a thread wait on a sync object tied to receiving data on the I2C bus.
Something like WaitForSingleObject() with a timeout.
I've seen the I2C samples for reading/writing to the DS1307, but they were all procedural calls with some Sleep() calls.
Also, do the ADS I2C drivers on WinCE support overlapped I/O? |
|
|
ctacke
877 Posts |
Posted - 29 Feb 2008 : 18:00:00
|
I'm not certain what you're asking. I2C is a master/slave bus, so to get data from a device, you must put data on the bus first. So you're not really polling, you're writing a command and then reading the response. See the sample I2C application, which has DS1307 sample code (and it doesn't use Sleep that I recall).
Also, what do you need overlapped I/O for? The I2C doesn't allow multiple devices talking at the same time, so I'm not certain what you'd need overlapped support for. |
 |
|
|
tscott
4 Posts |
Posted - 29 Feb 2008 : 18:34:03
|
Thanks for the reply.
Well, what happens if I do a read after writing a command, and the device doesn't reply because it's dead, bus error, who knows? Does the read block? Or do I just get back a buffer full of zeros (or garbage)?
I'm trying to program around some potential failure modes.
You're right, there isn't a sleep in DS1307. I think it's in in DeviceDetectionTest(), but I'm not sure why it's there. |
|
|
|
cbadr
154 Posts |
Posted - 04 Mar 2008 : 16:11:58
|
| As Chris has suggested, please take a look at the sample application code downloadable from topic 1402. It includes error codes and error handling examples. When a read operation fails, you usually receive a NACK or the operation times out, which can be captured by GetLastError() function. Please contact us if you need more specific help with designing your application. |
|
|
|
tscott
4 Posts |
Posted - 04 Mar 2008 : 18:09:50
|
| Great info, thanks to you both. |
|
|
| |
Topic |
|
|
|
All Forums
Hardware
WaitForSingleObject and I2C
Forum Locked
Send Topic to a Friend
Printer Friendly