ref: 61864557978b570d2364b36282b534c20d50bf46
parent: ea246c48c1df5d544c4521a5da81a8ddebcf7637
parent: efcca0ca7d23a006f148346186779a3ed64be0c5
author: jrmu <jrmu@cloud9p.org>
date: Sat Aug 31 12:42:57 EDT 2024
mkf's update to pi.ms
--- a/pi.ms
+++ b/pi.ms
@@ -11,8 +11,8 @@
.AE
.LP
-Raspberry pi is a single board computer made raspberry pi people
-somewhere in uk, in 2012(?) richard miller ported plan 9 port.
+Raspberry pi is a single board computer made by raspberry pi foundation
+somewhere in UK. In 2012(?) Richard miller have made the plan 9,
this is known as miller's pi. at some point 9front have imported miller's code.
9front have since got a 64-bit version of bcm kernel.
this guide covers 9front, more info on miller's is appercited.
@@ -22,7 +22,7 @@
As time of writing by default 9front ships with hjfs on installation image and that image is sized 2Gb.
You can dd (or cp, or whatever your prefered method may be) that into your sdcard.
That's all.
-.NH .1
+.SH
Resizing the paritions
.LP
Hjfs however does not support growing a parition (gefs seems to be the only file system capable of doing so),
@@ -38,21 +38,23 @@
run inst/start, make the partitions as you would on the sdcard, and install.
.NH
ISSUES
-.NH .1
+.SH
audio
.LP
-Pi is odd, audio hardware in pi is perhaps the most odd part of it.
+Raspberry Pi is odd, audio hardware in pi is perhaps the most odd part of it.
Use usb audio cards if you can, but if you can't:
.IP 1.
-3.5mm audio uses a PWM connected to arm core, and offers poor quality:
-but is much simpler. load on cpu sometimes casues noticable effects on PWM,
-and thus audiable and annoying noise.
+3.5MM jack uses a PWM connected to arm core, and offers poor quality.
+However it is much simpler to write a driver for.
+Load on cpu sometimes casues noticable effects on PWM,
+and thus results in audiable and annoying noises.
.IP 2.
HDMI audio is much more sophisticated (or horribly complex, depending on your point of view),
-and uses a RPC protocol to communicate with broadcom core. offers better audio.
+and uses a RPC protocol to communicate with broadcom core.
+which makes writing drivers much harder offers better audio.
.LP
There are two drivers for PWM, one is located under
-CW /n/extra/src/audiobcm.tgz
+.CW /n/extra/src/audiobcm.tgz
and said to be working for first pi (bcm2385).
I haven't tested it, but PWM audio interface have been realtively same since
bcm2385 (with some minor improvments) from arm core's view point.