2 * Copyright © 2012 Keith Packard <keithp@keithp.com>
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; version 2 of the License.
8 * This program is distributed in the hope that it will be useful, but
9 * WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
13 * You should have received a copy of the GNU General Public License along
14 * with this program; if not, write to the Free Software Foundation, Inc.,
15 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
20 * Reads a single byte from the shift register
24 #include <ao_74hc497.h>
30 ao_spi_get_bit(AO_74HC497_CS_PORT, AO_74HC497_CS_PIN, AO_74HC497_CS, AO_74HC497_SPI_BUS, AO_SPI_SPEED_FAST);
31 ao_spi_recv(&state, 1, AO_74HC497_SPI_BUS);
32 ao_spi_put_bit(AO_74HC497_CS_PORT, AO_74HC497_CS_PIN, AO_74HC497_CS, AO_74HC497_SPI_BUS);
41 v = ao_74hc497_read();
42 printf ("Switches: 0x%02x\n", v);
45 static const struct ao_cmds ao_74hc497_cmds[] = {
46 { ao_74hc497_cmd, "L\0Show 74hc497" },
53 ao_enable_output(AO_74HC497_CS_PORT, AO_74HC497_CS_PIN, AO_74HC497_CS, 1);
54 ao_cmd_register(&ao_74hc497_cmds[0]);