1 /*
2 * Copyright (c) 2015 Intel Corporation
3 *
4 * SPDX-License-Identifier: Apache-2.0
5 */
6
7 #include <errno.h>
8 #include <zephyr.h>
9 #include <sys/printk.h>
10 #include <device.h>
11 #include <drivers/i2c.h>
12
13 /**
14 * @file Sample app using the Fujitsu MB85RC256V FRAM through I2C.
15 */
16
17 #define FRAM_I2C_ADDR 0x50
18
write_bytes(const struct device * i2c_dev,uint16_t addr,uint8_t * data,uint32_t num_bytes)19 static int write_bytes(const struct device *i2c_dev, uint16_t addr,
20 uint8_t *data, uint32_t num_bytes)
21 {
22 uint8_t wr_addr[2];
23 struct i2c_msg msgs[2];
24
25 /* FRAM address */
26 wr_addr[0] = (addr >> 8) & 0xFF;
27 wr_addr[1] = addr & 0xFF;
28
29 /* Setup I2C messages */
30
31 /* Send the address to write to */
32 msgs[0].buf = wr_addr;
33 msgs[0].len = 2U;
34 msgs[0].flags = I2C_MSG_WRITE;
35
36 /* Data to be written, and STOP after this. */
37 msgs[1].buf = data;
38 msgs[1].len = num_bytes;
39 msgs[1].flags = I2C_MSG_WRITE | I2C_MSG_STOP;
40
41 return i2c_transfer(i2c_dev, &msgs[0], 2, FRAM_I2C_ADDR);
42 }
43
read_bytes(const struct device * i2c_dev,uint16_t addr,uint8_t * data,uint32_t num_bytes)44 static int read_bytes(const struct device *i2c_dev, uint16_t addr,
45 uint8_t *data, uint32_t num_bytes)
46 {
47 uint8_t wr_addr[2];
48 struct i2c_msg msgs[2];
49
50 /* Now try to read back from FRAM */
51
52 /* FRAM address */
53 wr_addr[0] = (addr >> 8) & 0xFF;
54 wr_addr[1] = addr & 0xFF;
55
56 /* Setup I2C messages */
57
58 /* Send the address to read from */
59 msgs[0].buf = wr_addr;
60 msgs[0].len = 2U;
61 msgs[0].flags = I2C_MSG_WRITE;
62
63 /* Read from device. STOP after this. */
64 msgs[1].buf = data;
65 msgs[1].len = num_bytes;
66 msgs[1].flags = I2C_MSG_READ | I2C_MSG_STOP;
67
68 return i2c_transfer(i2c_dev, &msgs[0], 2, FRAM_I2C_ADDR);
69 }
70
main(void)71 void main(void)
72 {
73 const struct device *i2c_dev = DEVICE_DT_GET(DT_NODELABEL(i2c0));
74 uint8_t cmp_data[16];
75 uint8_t data[16];
76 int i, ret;
77
78 if (!device_is_ready(i2c_dev)) {
79 printk("I2C: Device is not ready.\n");
80 return;
81 }
82
83 /* Do one-byte read/write */
84
85 data[0] = 0xAE;
86 ret = write_bytes(i2c_dev, 0x00, &data[0], 1);
87 if (ret) {
88 printk("Error writing to FRAM! error code (%d)\n", ret);
89 return;
90 } else {
91 printk("Wrote 0xAE to address 0x00.\n");
92 }
93
94 data[0] = 0x86;
95 ret = write_bytes(i2c_dev, 0x01, &data[0], 1);
96 if (ret) {
97 printk("Error writing to FRAM! error code (%d)\n", ret);
98 return;
99 } else {
100 printk("Wrote 0x86 to address 0x01.\n");
101 }
102
103 data[0] = 0x00;
104 ret = read_bytes(i2c_dev, 0x00, &data[0], 1);
105 if (ret) {
106 printk("Error reading from FRAM! error code (%d)\n", ret);
107 return;
108 } else {
109 printk("Read 0x%X from address 0x00.\n", data[0]);
110 }
111
112 data[1] = 0x00;
113 ret = read_bytes(i2c_dev, 0x01, &data[0], 1);
114 if (ret) {
115 printk("Error reading from FRAM! error code (%d)\n", ret);
116 return;
117 } else {
118 printk("Read 0x%X from address 0x01.\n", data[0]);
119 }
120
121 /* Do multi-byte read/write */
122
123 /* get some random data, and clear out data[] */
124 for (i = 0; i < sizeof(cmp_data); i++) {
125 cmp_data[i] = k_cycle_get_32() & 0xFF;
126 data[i] = 0x00;
127 }
128
129 /* write them to the FRAM */
130 ret = write_bytes(i2c_dev, 0x00, cmp_data, sizeof(cmp_data));
131 if (ret) {
132 printk("Error writing to FRAM! error code (%d)\n", ret);
133 return;
134 } else {
135 printk("Wrote %zu bytes to address 0x00.\n", sizeof(cmp_data));
136 }
137
138 ret = read_bytes(i2c_dev, 0x00, data, sizeof(data));
139 if (ret) {
140 printk("Error reading from FRAM! error code (%d)\n", ret);
141 return;
142 } else {
143 printk("Read %zu bytes from address 0x00.\n", sizeof(data));
144 }
145
146 ret = 0;
147 for (i = 0; i < sizeof(cmp_data); i++) {
148 /* uncomment below if you want to see all the bytes */
149 /* printk("0x%X ?= 0x%X\n", cmp_data[i], data[i]); */
150 if (cmp_data[i] != data[i]) {
151 printk("Data comparison failed @ %d.\n", i);
152 ret = -EIO;
153 }
154 }
155 if (ret == 0) {
156 printk("Data comparison successful.\n");
157 }
158 }
159
