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/*
* Copyright © 2013 Keith Packard <keithp@keithp.com>
*
* 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; version 2 of the License.
*
* 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.,
* 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
*/
/*
* 74HC165 driver.
* Reads a single byte from the shift register
*/
#include <ao.h>
#include <ao_74hc165.h>
uint8_t
ao_74hc165_read(void)
{
static __xdata state;
ao_spi_get(AO_74HC165_SPI_BUS);
ao_spi_set_speed(AO_74HC165_SPI_BUS, AO_SPI_SPEED_FAST);
AO_74HC165_CS = 1;
ao_spi_recv(&state, 1, AO_74HC165_SPI_BUS);
AO_74HC165_CS = 0;
ao_spi_put(AO_74HC165_SPI_BUS);
return state;
}
static void
ao_74hc165_cmd(void)
{
uint8_t v;
v = ao_74hc165_read();
printf ("Switches: 0x%02x\n", v);
}
static const struct ao_cmds ao_74hc165_cmds[] = {
{ ao_74hc165_cmd, "L\0Show 74hc165" },
{ 0, NULL }
};
void
ao_74hc165_init(void)
{
ao_enable_output(AO_74HC165_CS_PORT, AO_74HC165_CS_PIN, AO_74HC165_CS, 0);
ao_cmd_register(&ao_74hc165_cmds[0]);
}
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