Files
qmk_firmware/keyboards/massdrop/alt/spi.c
2019-04-16 09:24:38 -04:00

58 lines
2.7 KiB
C

/*
Copyright 2019 Massdrop Inc.
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, see <http://www.gnu.org/licenses/>.
*/
#include "arm_atsam_protocol.h"
void SR_EXP_Init_kb(void) {
/* Initialize shift register */
SR_EXP_OE_N_DIS;
SR_EXP_RCLK_HI;
SR_EXP_SERCOM->SPI.CTRLA.bit.DORD = 1; //Data Order - LSB is transferred first
SR_EXP_SERCOM->SPI.CTRLA.bit.CPOL = 1; //Clock Polarity - SCK high when idle. Leading edge of cycle is falling. Trailing rising.
SR_EXP_SERCOM->SPI.CTRLA.bit.CPHA = 1; //Clock Phase - Leading Edge Falling, change, Trailing Edge - Rising, sample
SR_EXP_SERCOM->SPI.CTRLA.bit.DIPO = 3; //Data In Pinout - SERCOM PAD[3] is used as data input (Configure away from DOPO. Not using input.)
SR_EXP_SERCOM->SPI.CTRLA.bit.DOPO = 0; //Data Output PAD[0], Serial Clock PAD[1]
SR_EXP_SERCOM->SPI.CTRLA.bit.MODE = 3; //Operating Mode - Master operation
SR_EXP_SERCOM->SPI.CTRLA.bit.ENABLE = 1; //Enable - Peripheral is enabled or being enabled
while (SR_EXP_SERCOM->SPI.SYNCBUSY.bit.ENABLE) { DBGC(DC_SPI_EXP_SYNC_ENABLING); }
/* Set default shift register values */
sr_exp_data.reg = 0; //Clear data register
sr_exp_data.bit.HUB_CONNECT = 0; //USB Hub disconnected
sr_exp_data.bit.HUB_RESET_N = 0; //USB Hub in reset state
sr_exp_data.bit.SRC_1 = 1; //Set CON1 CC A5/B5 as Rd 5.1k
sr_exp_data.bit.SRC_2 = 1; //Set CON2 CC A5/B5 as Rd 5.1k
sr_exp_data.bit.S_UP = 0; //Default USB data to CON1
sr_exp_data.bit.E_UP_N = 1; //Disable HOST
sr_exp_data.bit.S_DN1 = 1; //Default EXTRA port to CON2
sr_exp_data.bit.E_DN1_N = 1; //Disable EXTRA
sr_exp_data.bit.E_VBUS_1 = 0; //Disable CON1 5V
sr_exp_data.bit.E_VBUS_2 = 0; //Disable CON2 5V
sr_exp_data.bit.IRST = 1; //LED drivers I2C in reset
sr_exp_data.bit.SDB_N = 0; //LED drivers in shutdown
/* Write shift register data */
SR_EXP_WriteData();
/* Enable shift register output */
SR_EXP_OE_N_ENA;
}