diff options
author | Ralf Baechle <ralf@linux-mips.org> | 1997-12-16 06:32:09 +0000 |
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committer | Ralf Baechle <ralf@linux-mips.org> | 1997-12-16 06:32:09 +0000 |
commit | 1d68c48efe2d331857dfd4dfa4104fb366c100c5 (patch) | |
tree | e6c894ae6b00193b25948fa58cf596ee633053d7 /drivers/net/hamradio/soundmodem/sm_afsk2400_7.c | |
parent | aa944aa3453e47706685bc562711a9e87375941e (diff) |
Merge with Linux 2.1.72, part 3.
Diffstat (limited to 'drivers/net/hamradio/soundmodem/sm_afsk2400_7.c')
-rw-r--r-- | drivers/net/hamradio/soundmodem/sm_afsk2400_7.c | 296 |
1 files changed, 296 insertions, 0 deletions
diff --git a/drivers/net/hamradio/soundmodem/sm_afsk2400_7.c b/drivers/net/hamradio/soundmodem/sm_afsk2400_7.c new file mode 100644 index 000000000..d217936ab --- /dev/null +++ b/drivers/net/hamradio/soundmodem/sm_afsk2400_7.c @@ -0,0 +1,296 @@ +/*****************************************************************************/ + +/* + * sm_afsk2400_7.c -- soundcard radio modem driver, 2400 baud AFSK modem + * + * Copyright (C) 1996 Thomas Sailer (sailer@ife.ee.ethz.ch) + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + * + * Please note that the GPL allows you to use the driver, NOT the radio. + * In order to use the radio, you need a license from the communications + * authority of your country. + * + */ + +/* + * This driver is intended to be compatible with TCM3105 modems + * overclocked to 7.3728MHz. The mark and space frequencies therefore + * lie at 3658 and 1996 Hz. + * Note that I do _not_ recommend the building of such links, I provide + * this only for the users who live in the coverage area of such + * a "legacy" link. + */ + +#include "sm.h" +#include "sm_tbl_afsk2400_7.h" + +/* --------------------------------------------------------------------- */ + +struct demod_state_afsk24 { + unsigned int shreg; + unsigned int bit_pll; + unsigned char last_sample; + unsigned int dcd_shreg; + int dcd_sum0, dcd_sum1, dcd_sum2; + unsigned int dcd_time; + unsigned char last_rxbit; +}; + +struct mod_state_afsk24 { + unsigned int shreg; + unsigned char tx_bit; + unsigned int bit_pll; + unsigned int tx_seq; + unsigned int phinc; +}; + +/* --------------------------------------------------------------------- */ + +static const int dds_inc[2] = { AFSK24_TX_FREQ_LO*0x10000/AFSK24_SAMPLERATE, + AFSK24_TX_FREQ_HI*0x10000/AFSK24_SAMPLERATE }; + +static void modulator_2400_u8(struct sm_state *sm, unsigned char *buf, unsigned int buflen) +{ + struct mod_state_afsk24 *st = (struct mod_state_afsk24 *)(&sm->m); + + for (; buflen > 0; buflen--, buf++) { + if (st->tx_seq < 0x5555) { + if (st->shreg <= 1) + st->shreg = hdlcdrv_getbits(&sm->hdrv) | 0x10000; + st->tx_bit = (st->tx_bit ^ (!(st->shreg & 1))) & 1; + st->shreg >>= 1; + st->phinc = dds_inc[st->tx_bit & 1]; + } + st->tx_seq += 0x5555; + st->tx_seq &= 0xffff; + *buf = OFFSCOS(st->bit_pll); + st->bit_pll += st->phinc; + } +} + +/* --------------------------------------------------------------------- */ + +static void modulator_2400_s16(struct sm_state *sm, short *buf, unsigned int buflen) +{ + struct mod_state_afsk24 *st = (struct mod_state_afsk24 *)(&sm->m); + + for (; buflen > 0; buflen--, buf++) { + if (st->tx_seq < 0x5555) { + if (st->shreg <= 1) + st->shreg = hdlcdrv_getbits(&sm->hdrv) | 0x10000; + st->tx_bit = (st->tx_bit ^ (!(st->shreg & 1))) & 1; + st->shreg >>= 1; + st->phinc = dds_inc[st->tx_bit & 1]; + } + st->tx_seq += 0x5555; + st->tx_seq &= 0xffff; + *buf = COS(st->bit_pll); + st->bit_pll += st->phinc; + } +} + +/* --------------------------------------------------------------------- */ + +extern __inline__ int convolution14_u8(const unsigned char *st, const int *coeff, int csum) +{ + int sum = -0x80 * csum; + + sum += (st[0] * coeff[0]); + sum += (st[-1] * coeff[1]); + sum += (st[-2] * coeff[2]); + sum += (st[-3] * coeff[3]); + sum += (st[-4] * coeff[4]); + sum += (st[-5] * coeff[5]); + sum += (st[-6] * coeff[6]); + sum += (st[-7] * coeff[7]); + sum += (st[-8] * coeff[8]); + sum += (st[-9] * coeff[9]); + sum += (st[-10] * coeff[10]); + sum += (st[-11] * coeff[11]); + sum += (st[-12] * coeff[12]); + sum += (st[-13] * coeff[13]); + + sum >>= 7; + return sum * sum; +} + +extern __inline__ int convolution14_s16(const short *st, const int *coeff, int csum) +{ + int sum = 0; + + sum += (st[0] * coeff[0]); + sum += (st[-1] * coeff[1]); + sum += (st[-2] * coeff[2]); + sum += (st[-3] * coeff[3]); + sum += (st[-4] * coeff[4]); + sum += (st[-5] * coeff[5]); + sum += (st[-6] * coeff[6]); + sum += (st[-7] * coeff[7]); + sum += (st[-8] * coeff[8]); + sum += (st[-9] * coeff[9]); + sum += (st[-10] * coeff[10]); + sum += (st[-11] * coeff[11]); + sum += (st[-12] * coeff[12]); + sum += (st[-13] * coeff[13]); + + sum >>= 15; + return sum * sum; +} + +extern __inline__ int do_filter_2400_u8(const unsigned char *buf) +{ + int sum = convolution14_u8(buf, afsk24_tx_lo_i, SUM_AFSK24_TX_LO_I); + sum += convolution14_u8(buf, afsk24_tx_lo_q, SUM_AFSK24_TX_LO_Q); + sum -= convolution14_u8(buf, afsk24_tx_hi_i, SUM_AFSK24_TX_HI_I); + sum -= convolution14_u8(buf, afsk24_tx_hi_q, SUM_AFSK24_TX_HI_Q); + return sum; +} + +extern __inline__ int do_filter_2400_s16(const short *buf) +{ + int sum = convolution14_s16(buf, afsk24_tx_lo_i, SUM_AFSK24_TX_LO_I); + sum += convolution14_s16(buf, afsk24_tx_lo_q, SUM_AFSK24_TX_LO_Q); + sum -= convolution14_s16(buf, afsk24_tx_hi_i, SUM_AFSK24_TX_HI_I); + sum -= convolution14_s16(buf, afsk24_tx_hi_q, SUM_AFSK24_TX_HI_Q); + return sum; +} + +/* --------------------------------------------------------------------- */ + +static void demodulator_2400_u8(struct sm_state *sm, const unsigned char *buf, unsigned int buflen) +{ + struct demod_state_afsk24 *st = (struct demod_state_afsk24 *)(&sm->d); + int j; + int sum; + unsigned char newsample; + + for (; buflen > 0; buflen--, buf++) { + sum = do_filter_2400_u8(buf); + st->dcd_shreg <<= 1; + st->bit_pll += AFSK24_BITPLL_INC; + newsample = (sum > 0); + if (st->last_sample ^ newsample) { + st->last_sample = newsample; + st->dcd_shreg |= 1; + if (st->bit_pll < (0x8000+AFSK24_BITPLL_INC/2)) + st->bit_pll += AFSK24_BITPLL_INC/2; + else + st->bit_pll -= AFSK24_BITPLL_INC/2; + j = /* 2 * */ hweight8(st->dcd_shreg & 0x1c) + - hweight16(st->dcd_shreg & 0x1e0); + st->dcd_sum0 += j; + } + hdlcdrv_channelbit(&sm->hdrv, st->last_sample); + if ((--st->dcd_time) <= 0) { + hdlcdrv_setdcd(&sm->hdrv, (st->dcd_sum0 + + st->dcd_sum1 + + st->dcd_sum2) < 0); + st->dcd_sum2 = st->dcd_sum1; + st->dcd_sum1 = st->dcd_sum0; + st->dcd_sum0 = 2; /* slight bias */ + st->dcd_time = 120; + } + if (st->bit_pll >= 0x10000) { + st->bit_pll &= 0xffff; + st->shreg >>= 1; + st->shreg |= (!(st->last_rxbit ^ + st->last_sample)) << 16; + st->last_rxbit = st->last_sample; + diag_trigger(sm); + if (st->shreg & 1) { + hdlcdrv_putbits(&sm->hdrv, st->shreg >> 1); + st->shreg = 0x10000; + } + } + diag_add(sm, (((int)*buf)-0x80) << 8, sum); + } +} + +/* --------------------------------------------------------------------- */ + +static void demodulator_2400_s16(struct sm_state *sm, const short *buf, unsigned int buflen) +{ + struct demod_state_afsk24 *st = (struct demod_state_afsk24 *)(&sm->d); + int j; + int sum; + unsigned char newsample; + + for (; buflen > 0; buflen--, buf++) { + sum = do_filter_2400_s16(buf); + st->dcd_shreg <<= 1; + st->bit_pll += AFSK24_BITPLL_INC; + newsample = (sum > 0); + if (st->last_sample ^ newsample) { + st->last_sample = newsample; + st->dcd_shreg |= 1; + if (st->bit_pll < (0x8000+AFSK24_BITPLL_INC/2)) + st->bit_pll += AFSK24_BITPLL_INC/2; + else + st->bit_pll -= AFSK24_BITPLL_INC/2; + j = /* 2 * */ hweight8(st->dcd_shreg & 0x1c) + - hweight16(st->dcd_shreg & 0x1e0); + st->dcd_sum0 += j; + } + hdlcdrv_channelbit(&sm->hdrv, st->last_sample); + if ((--st->dcd_time) <= 0) { + hdlcdrv_setdcd(&sm->hdrv, (st->dcd_sum0 + + st->dcd_sum1 + + st->dcd_sum2) < 0); + st->dcd_sum2 = st->dcd_sum1; + st->dcd_sum1 = st->dcd_sum0; + st->dcd_sum0 = 2; /* slight bias */ + st->dcd_time = 120; + } + if (st->bit_pll >= 0x10000) { + st->bit_pll &= 0xffff; + st->shreg >>= 1; + st->shreg |= (!(st->last_rxbit ^ + st->last_sample)) << 16; + st->last_rxbit = st->last_sample; + diag_trigger(sm); + if (st->shreg & 1) { + hdlcdrv_putbits(&sm->hdrv, st->shreg >> 1); + st->shreg = 0x10000; + } + } + diag_add(sm, *buf, sum); + } +} + +/* --------------------------------------------------------------------- */ + +static void demod_init_2400(struct sm_state *sm) +{ + struct demod_state_afsk24 *st = (struct demod_state_afsk24 *)(&sm->d); + + st->dcd_time = 120; + st->dcd_sum0 = 2; +} + +/* --------------------------------------------------------------------- */ + +const struct modem_tx_info sm_afsk2400_7_tx = { + "afsk2400_7", sizeof(struct mod_state_afsk24), AFSK24_SAMPLERATE, 2400, + modulator_2400_u8, modulator_2400_s16, NULL +}; + +const struct modem_rx_info sm_afsk2400_7_rx = { + "afsk2400_7", sizeof(struct demod_state_afsk24), + AFSK24_SAMPLERATE, 2400, 14, AFSK24_SAMPLERATE/2400, + demodulator_2400_u8, demodulator_2400_s16, demod_init_2400 +}; + +/* --------------------------------------------------------------------- */ |