Wiki tutorial on SPI
#1
Posted 01 September 2011 - 11:11 AM
I improved the existing SPI Confiugration tutorial by MikeP.
I would ask to anyone of (US) English mother-language to check and edit for correctness.
Nothing versus the British English, but it seems to me that most of the tech-literature is offered in US English.
Thank you all.
Cheers
#2
Posted 01 September 2011 - 11:39 AM
My .NETMF projects: .NETMF Toolbox / Gadgeteer Light / Some PCB designs
#3
Posted 01 September 2011 - 12:16 PM
#4
Posted 01 September 2011 - 02:54 PM
Preparing for a vacation, but my postcount is a bit lower as usual indeedStefan!...Were you on vacation?
It's a been that I did not see any post from you...
Working on a few things, of which I will release one hopefully next week on the boards.
My .NETMF projects: .NETMF Toolbox / Gadgeteer Light / Some PCB designs
#5
Posted 01 September 2011 - 04:18 PM
I would add a section for the HC165 as well.
Do you think would be better to move as a separate tutorial?
It seems to me that the users are asking always the same questions. For instance, they're asking about the UART, and there's no any tutorial on it.
Maybe I will do it.
Our prime minister (and the rest of gov) is specialized on economic sciences.Preparing for a vacation, but my postcount is a bit lower as usual indeed
He has created the 'HC595-bank-account for the citizens. You put inside your Euro, on the (many) outputs there are a bunch of "smart" people pulling out many Euros. The main problem is that they're pulling out much more than you push inside...new kind of FIFO?
Have fun!
Cheers
#6
Posted 04 September 2011 - 01:37 AM
#7
Posted 04 September 2011 - 06:25 AM
Okay, I'll move it off.I think that a tutorial on using the 74HC595 is worthy of being a wiki topic in its own right.
Can I suggest that you copy the tutorial to a new topic and link to that from the SPI configuration topic.
That's right: there's a mistake.This bit is not quite correct:
"In the below picture there are the four possible combinations of Clock_Edge (NCPHA) and Clock_Idle (CPOL)"
The NCPHA and CPOL bits used by the processor to control the SPI transfer do not map directly to the Clock_Edge and Clock_Idle parameters.
It is not true to say that Clock_Edge==NCPHA. If CPOL==1 then Clock_Edge = !NCPHA
It is correct that CPOL and NCPHA select 1 of four SPI modes and Clock_Edge and Clock_Idle have the same function.
Anyway, I'm not sure about what you mean. Clock_Edge and Clock_Idle are not the same.
I checked it as:
- CPOL == Clock_Idle
- NCPHA == Clock_Idle XOR Clock_Edge
- Clock_Idle == CPOL
- Clock_Edge == CPOL XOR NCPHA
From my viewpoint, this tutorial wouldn't have sense if the people are able to understand the datasheet. What I have seen, it's just they are making confusion...and there's no any table showing how to relate the chip logic to the software flags.It would be better to show an excerpt from the 74HC595 datasheet and highlight what to look for.
For instance, your SPI config description is valuable, but it does not clarify how to set the flags upon a certain chip (e.g. 74HC595). The typical user does not want to squeeze its brain, but it prefers having some kind of walkthrough.
I'm not sure a datasheet excerpt would simplify the user's comprehension.
Anyway, the Wiki is free for anyone who likes to improve it.
Cheers
#8
Posted 04 September 2011 - 12:31 PM
0 user(s) are reading this topic
0 members, 0 guests, 0 anonymous users