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gebi / AGPS.md
Created Mar 26, 2021 — forked from veproza/AGPS.md
Getting u-blox MAX-7C GPS to work with Assisted A-GPS
View AGPS.md

Getting u-blox MAX-7C GPS to work with Assisted A-GPS

So you got your u-blox GPS and wired it up only to look at it struggling to get a valid fix? Under less than ideal conditions, it can take a better part of half an hour. That's because unlike your smartphone GPS, it doesn't have the luxury of having downloaded all the auxiliary navigation data (almanacs and the lot) out-of-band, via fast mobile connection. Instead it relies on the satellite's signal itself, which is being transmitted to you at meager 50 bits per second (I'm not missing "kilo" there, it's three orders of magnitude slower than your 2G GPRS connection).

Luckily, the u-blox receivers are fitted with what the company calls "AssistNow" capability and it does exactly the same thing your iPhone does - feeds the GPS with pre-downloaded almanacs, speeding up the acquisition process to mere seconds.

In principle, the process looks easy enough - we just need to download the data, and then push them to the receiver. Sadly, the AssistNow documentat

@gebi
gebi / diskchecker.pl
Created Mar 5, 2021 — forked from bradfitz/diskchecker.pl
diskchecker.pl
View diskchecker.pl
#!/usr/bin/perl
#
# Brad's el-ghetto do-our-storage-stacks-lie?-script
#
sub usage {
die <<'END';
Usage: diskchecker.pl -s <server[:port]> verify <file>
diskchecker.pl -s <server[:port]> create <file> <size_in_MB>
diskchecker.pl -l [port]
@gebi
gebi / psql_internals_cheatsheet.sql
Created Mar 5, 2021 — forked from azet/psql_internals_cheatsheet.sql
PostgreSQL internals SQL collection
View psql_internals_cheatsheet.sql
# long running queries:
SELECT
pid,
now() - pg_stat_activity.query_start AS duration,
query,
state
FROM pg_stat_activity
WHERE (now() - pg_stat_activity.query_start) > interval '5 minutes';
## active queries and killing them:
View es_index_maintenance.js
#!/usr/bin/env node
// Configuration
var argv = require('optimist')
.usage('Usage: $0 --prefix index_prefix [options]')
.demand(['prefix'])
.describe({
host: 'Elastic Search host',
port: 'Elastic Search port',
secure: 'Use secure Elastic Search connection',
View avcodec.c
#define __USE_GNU
#define _GNU_SOURCE
#include <pthread.h>
#include <stdio.h>
#include <stdint.h>
#include <string.h>
#include "erl_nif.h"
#include "frog_draw.h"