view uptools/libcoding/gsm7_unpack.c @ 1001:7df4c9ae6ba4

loadtools/scripts: w220.{config,init} => chimei.{config,init} Motorola W220, first touched by FreeCalypso in 2019-05, is an ODM phone made by Chi-Mei, and its peculiar property of relevance to loadtools is that it has XRAM on Calypso nCS3 instead of the usual nCS1 - which matters for fc-xram. We are now discovering other Chi-Mei phones including Sony Ericsson J120, and they share the same quirk of XRAM on nCS3 - hence we rename this loadtools target from w220 to chimei.
author Mychaela Falconia <falcon@freecalypso.org>
date Sat, 09 Dec 2023 17:53:44 +0000
parents d29b45c4c8db
children
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/*
 * This library module implements unpacking of GSM 7-bit data
 * from packed octets.
 */

#include <sys/types.h>

static u_char shift[8] = {0, 7, 6, 5, 4, 3, 2, 1};

gsm7_unpack(inbuf, outbuf, nseptets)
	u_char *inbuf, *outbuf;
	unsigned nseptets;
{
	u_char *inp = inbuf, *outp = outbuf;
	unsigned n;

	for (n = 0; n < nseptets; n++) {
		*outp++ = (((inp[1] << 8) | inp[0]) >> shift[n&7]) & 0x7F;
		if (n & 7)
			inp++;
	}
}