LPCXpresso IDEのトピックRe: I2C code examples - do they work?

I2C code examples - do they work?

lpcware — Wed, 15 Jun 2016 22:04:56 GMT

Content originally posted in LPCWare by woodchuck on Sun Aug 01 13:56:54 MST 2010
From the "README" file, I conclude that the two I2C sample programs (named I2C and I2CSlave) are designed to "talk" to each other. Does this involved loading the I2C project on one board and the I2CSlave project on the other board? Or does one load the I2C project to both boards?

Is the silk screen legend correct regarding the location of the SCL and SDA pins on the LPCxpresso boards?

Short of an oscilloscope, is there any way of telling whether the desired transfer has taken place? I see no activity with my scope.

FWIW, I am using 5.5K pull-up resistors to 3.3 V, and I have a very competent ground wire running between the two boards.

Re: I2C code examples - do they work?

lpcware — Wed, 15 Jun 2016 22:04:57 GMT

Content originally posted in LPCWare by NXP_Europe on Sun Aug 01 14:40:20 MST 2010
[B]Hello Woodchuck,[/B]

[I]From the "README" file, I conclude that the two I2C sample programs (named I2C and I2CSlave) are designed to "talk" to each other. Does this involved loading the I2C project on one board and the I2CSlave project on the other board? Or does one load the I2C project to both boards?[/I]

[B]Under normal circumstances, when I2C-communication is taken place, one Master is on the bus and at least one Slave. In your case it will not be different. In practice it means that in one controller the Master program is running and in the other the Slave program.[/B]

[I]Is the silk screen legend correct regarding the location of the SCL and SDA pins on the LPCxpresso boards?[/I]

[B]Should be o.k. do you have reason to belief that it is not?[/B]
[B]The connections between the boards should be: gnd <=> gnd, SCl <=> SCl and SDa <=> SDa.[/B]

[I]Short of an oscilloscope, is there any way of telling whether the desired transfer has taken place? I see no activity with my scope.[/I]

[B]Make the transferspeed as slow as possible. Use led's on the signal lines.[/B]

[I]FWIW, I am using 5.5K pull-up resistors to 3.3 V, and I have a very competent ground wire running between the two boards. [/I]

[B]Should be o.k.[/B]

Re: I2C code examples - do they work?

lpcware — Wed, 15 Jun 2016 22:04:57 GMT

Content originally posted in LPCWare by woodchuck on Mon Aug 02 12:34:10 MST 2010
Thank you! LED's were a great idea. I see that the code works, now. And I see how the code works. It took me a few readings - or at least one CAREFUL reading.