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[system_information] fix bit map 0 frequency list generation 

Our frequency lists for GSM900 were completely wrong, as the bit map 0
encoding was not used correctly.  This patch should fix it.
This commit is contained in:
Harald Welte 2009-12-14 20:25:05 +01:00
parent 1e191c59f6
commit da760d3d19
1 changed files with 9 additions and 2 deletions
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11
openbsc/src/system_information.c
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@ -35,21 +35,28 @@
#define GSM_MACBLOCK_LEN 23
#define GSM_MACBLOCK_PADDING 0x2b
/* Frequency Lists as per TS 04.08 10.5.2.13 */
/* 10.5.2.13.2: Bit map 0 format */
static int cchan_list_bm0_set_arfcn(u_int8_t *chan_list, unsigned int arfcn)
{
unsigned int byte, bit;
if (arfcn > 124)
if (arfcn > 124 || arfcn < 1)
return -EINVAL;
/* the bitmask is from 1..124, not from 0..123 */
arfcn--;
byte = arfcn / 8;
bit = arfcn % 8;
chan_list[GSM48_CELL_CHAN_DESC_SIZE-byte] |= (1 << bit);
chan_list[GSM48_CELL_CHAN_DESC_SIZE-1-byte] |= (1 << bit);
return 0;
}
/* 10.5.2.13.7: Variable bit map format */
static int cchan_list_bmrel_set_arfcn(u_int8_t *chan_list, unsigned int arfcn)
{
unsigned int byte, bit;