Revision: 1154
Author: sebastien.lelong
Date: Mon Aug 3 10:30:26 2009
Log: Edited wiki page through web user interface.
http://code.google.com/p/jallib/source/detail?r=1154
Modified:
/wiki/UpdatingPinmap.wiki
=======================================
--- /wiki/UpdatingPinmap.wiki Mon Aug 3 08:55:41 2009
+++ /wiki/UpdatingPinmap.wiki Mon Aug 3 10:30:26 2009
@@ -3,19 +3,19 @@
= What's pinmap ? =
-*pinmap.json* is a file containing all pin definitions & aliases. As you
know, given a PIC, each of its pins can have multiple functionality. For
instance, one pin can be involved in ADC conversion, serial comms, i2c,
etc... Depending on the functionality, its name can vary. The purpose of
this file is to describe, for each PIC, for each pin, what are the aliases.
-
-Format is JSON. It's a very simple format, human-readable.
+*pinmap.py* is a file containing all pin definitions & aliases. As you
know, given a PIC, each of its pins can have multiple functionality. For
instance, one pin can be involved in ADC conversion, serial comms, i2c,
etc... Depending on the functionality, its name can vary. The purpose of
this file is to describe, for each PIC, for each pin, what are the aliases.
+
+Format is a python dictionary. It's a very simple format, human-readable.
= Why ? What is it used for ? =
Creating and maintaining this file is highly time-consuming. You may
ask "why are you doing this guys ? Can't you get this information from
somewhere at Microchip ?". No it seems not. (but if you aware of something,
please report...). At the beginning, this file was produced by parsing
datasheets (see ParsingDatasheets), but this was a one-shot approach,
highly fragile. By that times, gods were with us and it was working. Now
they have seem to have left us, with a cursed burden: update maintenance...
-This pinmap.json file is then used to produce many derivative files. All
aliases are also available from device files, and may be involved libraries
such as ADC for instance.
+This pinmap.py file is then used to produce many derivative files. All
aliases are also available from device files, and may be involved libraries
such as ADC for instance. These derivative files are also JSON versions of
this python file, a format parsable in many language (note: python file
remains the pristine source, mostly because you can add comments in it and
because dict's keys can be lists, not just strings).
-= "I don't know what to do during my days, I want to help and feed
pinmap.json !" =
+= "I don't know what to do during my days, I want to help and feed
pinmap.py !" =
OK, welcome to hell... hum... here !
@@ -23,47 +23,56 @@
Anyway, we're about lower energy of the Universe and slow down this
increasing entropy by fixing things for this PIC.
-Open pinmap.json file, with favorite editor. A PIC entry looks like:
+Open pinmap.py file, with favorite editor. A PIC entry looks like:
{{{
- "10F200": {
- "RA0": [
- "GP0",
- "ICSPDAT"
- ],
- "RA1": [
- "GP1",
- "ICSPCLK"
- ],
- "RA2": [
- "GP2",
- "T0CKI",
- "FOSC4"
- ],
- "RA3": [
- "GP3",
- "MCLR",
- "VPP"
- ]
- }
+{'10F200': {'RA0': ['GP0', 'ICSPDAT'],
+ 'RA1': ['GP1', 'ICSPCLK'],
+ 'RA2': ['GP2', 'T0CKI', 'FOSC4'],
+ 'RA3': ['GP3', 'MCLR', 'VPP']}
}}}
-It looks like a python dictionary for those who know. It reads like: for
PIC named "10F200", there's a first pin named "RA0" for which there are two
aliases, "GP0" and "ICSPDAT". All this information is available by reading
pin diagram for the given PIC.
+This is a python dictionary for those who know. It reads like: for PIC
named "10F200", there's a first pin named "RA0" for which there are two
aliases, "GP0" and "ICSPDAT". All this information is available by reading
pin diagram for the given PIC.
Note "RA0" comes from the device file: there's no RA0 pin in datasheet,
but all pins are normalized to this naming convention.
-Now open 16F722 datasheet, read the pin diagram for it, and adjust things
in pinmap.json. Once you're done, save it, and check things are formatted
correctly. For this, you can open this JSON file using any parser. For
python, you can use "simplejson":
+Now open 16F722 datasheet, read the pin diagram for it, and adjust things
in pinmap.py. Once you're done, save it, and check things are formatted
correctly. For this, you can just import your pinmap.py
{{{
-python> import simplejson
-python> pinmap = simplejson.load(file("pinmap.json"))
+python> import pinmap
python>
}}}
-Any error ? Make sure you did not forget any double quotes, commas, etc...
If no error occured, you're not done yet, now you have to make
sure "adc_pcfg.json" file is also up-to-date. "Hey, I did not sign for thi
s !". Too late, you too are cursed, you need to get things done 'til the
end ! If the PIC has PCFG bits, you may have to fill "adc_pcfg.json". If
not, just jump to the last action.
+Any error ? Make sure you did not forget any quotes, commas, etc... If no
error occured, you're not done yet, now you have to make sure "adc_pcfg.py"
file is also up-to-date, located in "tools/adc". "Hey, I did not sign for
this !", I can hear. Too late, you too are cursed, you need to get things
done 'til the end ! If the PIC has PCFG bits, you may have to
fill "adc_pcfg.py". If not, just jump to the last action.
If you look at 16F877 datasheet and look for "PCFG", you'll find a big
table where PCFG bits combinations are listed to configure ADC pins. This
is what you have to transcribe here. In this file, things are listed by
datasheet references, not by PIC. Find your reference by looking at
PicGroups. you may just have nothing to do, but just make sure things are
ok for your PIC.
+Here an example of content, showing one combination:
+
+{{{
+ '30491C' : {
+ '0000' : {
+ 'AN15/RH7' : 'A',
+ 'AN14/RH6' : 'A',
+ 'AN13/RH5' : 'A',
+ 'AN12/RH4' : 'A',
+ 'AN11/RF6' : 'A',
+ 'AN10/RF5' : 'A',
+ 'AN9/RF4' : 'A',
+ 'AN8/RF3' : 'A',
+ 'AN7/RF2' : 'A',
+ 'AN6/RF1' : 'A',
+ 'AN5/RF0' : 'A',
+ 'AN4/RA5' : 'A',
+ 'AN3/RA3' : 'A',
+ 'AN2/RA2' : 'A',
+ 'AN1/RA1' : 'A',
+ 'AN0/RA0' : 'A'
+}}}
+
+It reads: for datasheet reference 30491C, when PCGF bits equals 0b_0000,
then all pins (AN15/... to AN0/...) are analog (A). "D" means digital.
Sometimes, pins are named just "RA0" instead of "AN0/RA0". This is because
datasheets refer them using these two notations. But remember,
in "AN0/RA0", the analog part ("AN0") is before "/".
+
+
Last action, generate all derivate files:
{{{
@@ -72,5 +81,3 @@
You're done, you're brave.
-
-
--~--~---------~--~----~------------~-------~--~----~
You received this message because you are subscribed to the Google Groups
"jallib" group.
To post to this group, send email to [email protected]
To unsubscribe from this group, send email to
[email protected]
For more options, visit this group at
http://groups.google.com/group/jallib?hl=en
-~----------~----~----~----~------~----~------~--~---
