ARMmbed
/
mbed-os
mirror of https://github.com/ARMmbed/mbed-os.git
1
0
Fork 0
Code Issues Projects Releases Wiki Activity

Initial commit of the I2C EEPROM device

pull/10711/head
Christopher Haster 2017-02-14 11:29:39 -06:00
commit ec88f7822f
5 changed files with 641 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

138
I2CEEBlockDevice.cpp Normal file
View File

@ -0,0 +1,138 @@
/* Simple access class for I2C EEPROM chips like Microchip 24LC
* Copyright (c) 2015 Robin Hourahane
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "I2CEEBlockDevice.h"
#define I2CEE_TIMEOUT 10000
I2CEEBlockDevice::I2CEEBlockDevice(
PinName sda, PinName scl, uint8_t addr,
bd_size_t size, bd_size_t block, int freq)
: _i2c(sda, scl), _i2c_addr(addr), _size(size), _block(block)
{
_i2c.frequency(freq);
}
bd_error_t I2CEEBlockDevice::init()
{
return _sync();
}
bd_error_t I2CEEBlockDevice::deinit()
{
return 0;
}
bd_error_t I2CEEBlockDevice::read(void *buffer, bd_addr_t addr, bd_size_t size)
{
// Check the address and size fit onto the chip.
if (!is_valid_read(addr, size)) {
return BD_ERROR_PARAMETER;
}
_i2c.start();
if (!_i2c.write(_i2c_addr | 0) ||
!_i2c.write((char)(addr >> 8)) ||
!_i2c.write((char)(addr & 0xff))) {
return BD_ERROR_DEVICE_ERROR;
}
_i2c.stop();
if (_i2c.read(_i2c_addr, static_cast<char*>(buffer), size) < 0) {
return BD_ERROR_DEVICE_ERROR;
}
return 0;
}
bd_error_t I2CEEBlockDevice::program(const void *buffer, bd_addr_t addr, bd_size_t size)
{
// Check the addr and size fit onto the chip.
if (!is_valid_program(addr, size)) {
return BD_ERROR_PARAMETER;
}
// While we have some more data to write.
while (size > 0) {
uint32_t off = addr % _block;
uint32_t chunk = (off + size < _block) ? size : (_block - off);
_i2c.start();
if (!_i2c.write(_i2c_addr | 0) ||
!_i2c.write((char)(addr >> 8)) ||
!_i2c.write((char)(addr & 0xff))) {
return BD_ERROR_DEVICE_ERROR;
}
for (unsigned i = 0; i < chunk; i++) {
_i2c.write(static_cast<const char*>(buffer)[i]);
}
_i2c.stop();
bd_error_t err = _sync();
if (err) {
return err;
}
addr += chunk;
size -= chunk;
buffer = static_cast<const char*>(buffer) + chunk;
}
return 0;
}
bd_error_t I2CEEBlockDevice::erase(bd_addr_t addr, bd_size_t size)
{
// No erase needed
return 0;
}
bd_error_t I2CEEBlockDevice::_sync()
{
// The chip doesn't ACK while writing to the actual EEPROM
// so loop trying to do a zero byte write until it is ACKed
// by the chip.
for (int i = 0; i < I2CEE_TIMEOUT; i++) {
if (_i2c.write(_i2c_addr | 0, 0, 0) < 1) {
return 0;
}
wait_ms(1);
}
return BD_ERROR_DEVICE_ERROR;
}
bd_size_t I2CEEBlockDevice::get_read_size()
{
return 1;
}
bd_size_t I2CEEBlockDevice::get_program_size()
{
return 1;
}
bd_size_t I2CEEBlockDevice::get_erase_size()
{
return 1;
}
bd_size_t I2CEEBlockDevice::size()
{
return _size;
}

149
I2CEEBlockDevice.h Normal file
View File

@ -0,0 +1,149 @@
/* Simple access class for I2C EEPROM chips like Microchip 24LC
* Copyright (c) 2015 Robin Hourahane
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef MBED_I2CEEPROM_BLOCK_DEVICE_H
#define MBED_I2CEEPROM_BLOCK_DEVICE_H
/* If the target has no I2C support then I2CEEPROM is not supported */
#ifdef DEVICE_I2C
#include <mbed.h>
#include "BlockDevice.h"
/** BlockDevice for I2C based flash device such as
* Microchip's 24LC or ATMEL's AT24C ranges
*
* @code
* #include "mbed.h"
* #include "I2CEEBlockDevice.h"
*
* // Create 24LC device with 32Kbytes of memory
* I2CEEBlockDevice flash(D14, D15, 0xa0, 32*1024);
*
* int main() {
* printf("flash test\n");
* mx52r.init();
* printf("flash size: %llu\n", flash.size());
* printf("flash read size: %llu\n", flash.get_read_size());
* printf("flash program size: %llu\n", flash.get_program_size());
* printf("flash erase size: %llu\n", flash.get_erase_size());
*
* uint8_t *buffer = malloc(flash.get_erase_size());
* sprintf(buffer, "Hello World!\n");
* flash.erase(0, flash.get_erase_size());
* flash.program(buffer, 0, flash.get_erase_size());
* flash.read(buffer, 0, flash.get_erase_size());
* printf("%s", buffer);
*
* flash.deinit();
* }
*/
class I2CEEBlockDevice : public BlockDevice {
public:
/** Constructor to create an I2CEEBlockDevice on I2C pins
*
* @param sda The pin name for the sda line of the I2C bus.
* @param scl The pin name for the scl line of the I2C bus.
* @param addr The 8bit I2C address of the chip, common range 0xa0 - 0xae.
* @param size The size of the device in bytes
* @param block The page size of the device in bytes, defaults to 32bytes
* @param freq The frequency of the I2C bus, defaults to 400K.
*/
I2CEEBlockDevice(
PinName sda, PinName scl, uint8_t address,
bd_size_t size, bd_size_t block=32,
int bus_speed=400000);
/** Initialize a block device
*
* @return 0 on success or a negative error code on failure
*/
virtual bd_error_t init();
/** Deinitialize a block device
*
* @return 0 on success or a negative error code on failure
*/
virtual bd_error_t deinit();
/** Read blocks from a block device
*
* @param buffer Buffer to write blocks to
* @param addr Address of block to begin reading from
* @param size Size to read in bytes, must be a multiple of read block size
* @return 0 on success, negative error code on failure
*/
virtual bd_error_t read(void *buffer, bd_addr_t addr, bd_size_t size);
/** Program blocks to a block device
*
* The blocks must have been erased prior to being programmed
*
* @param buffer Buffer of data to write to blocks
* @param addr Address of block to begin writing to
* @param size Size to write in bytes, must be a multiple of program block size
* @return 0 on success, negative error code on failure
*/
virtual bd_error_t program(const void *buffer, bd_addr_t addr, bd_size_t size);
/** Erase blocks on a block device
*
* The state of an erased block is undefined until it has been programmed
*
* @param addr Address of block to begin erasing
* @param size Size to erase in bytes, must be a multiple of erase block size
* @return 0 on success, negative error code on failure
*/
virtual bd_error_t erase(bd_addr_t addr, bd_size_t size);
/** Get the size of a readable block
*
* @return Size of a readable block in bytes
*/
virtual bd_size_t get_read_size();
/** Get the size of a programable block
*
* @return Size of a programable block in bytes
* @note Must be a multiple of the read size
*/
virtual bd_size_t get_program_size();
/** Get the size of a eraseable block
*
* @return Size of a eraseable block in bytes
* @note Must be a multiple of the program size
*/
virtual bd_size_t get_erase_size();
/** Get the total size of the underlying device
*
* @return Size of the underlying device in bytes
*/
virtual bd_size_t size();
private:
I2C _i2c;
uint8_t _i2c_addr;
uint32_t _size;
uint32_t _block;
bd_error_t _sync();
};
#endif /* DEVICE_SPI */
#endif /* MBED_SD_BLOCK_DEVICE_H */

165
LICENSE Normal file
View File

@ -0,0 +1,165 @@
Apache License
Version 2.0, January 2004
http://www.apache.org/licenses/
TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
1. Definitions.
"License" shall mean the terms and conditions for use, reproduction, and
distribution as defined by Sections 1 through 9 of this document.
"Licensor" shall mean the copyright owner or entity authorized by the copyright
owner that is granting the License.
"Legal Entity" shall mean the union of the acting entity and all other entities
that control, are controlled by, or are under common control with that entity.
For the purposes of this definition, "control" means (i) the power, direct or
indirect, to cause the direction or management of such entity, whether by
contract or otherwise, or (ii) ownership of fifty percent (50%) or more of the
outstanding shares, or (iii) beneficial ownership of such entity.
"You" (or "Your") shall mean an individual or Legal Entity exercising
permissions granted by this License.
"Source" form shall mean the preferred form for making modifications, including
but not limited to software source code, documentation source, and configuration
files.
"Object" form shall mean any form resulting from mechanical transformation or
translation of a Source form, including but not limited to compiled object code,
generated documentation, and conversions to other media types.
"Work" shall mean the work of authorship, whether in Source or Object form, made
available under the License, as indicated by a copyright notice that is included
in or attached to the work (an example is provided in the Appendix below).
"Derivative Works" shall mean any work, whether in Source or Object form, that
is based on (or derived from) the Work and for which the editorial revisions,
annotations, elaborations, or other modifications represent, as a whole, an
original work of authorship. For the purposes of this License, Derivative Works
shall not include works that remain separable from, or merely link (or bind by
name) to the interfaces of, the Work and Derivative Works thereof.
"Contribution" shall mean any work of authorship, including the original version
of the Work and any modifications or additions to that Work or Derivative Works
thereof, that is intentionally submitted to Licensor for inclusion in the Work
by the copyright owner or by an individual or Legal Entity authorized to submit
on behalf of the copyright owner. For the purposes of this definition,
"submitted" means any form of electronic, verbal, or written communication sent
to the Licensor or its representatives, including but not limited to
communication on electronic mailing lists, source code control systems, and
issue tracking systems that are managed by, or on behalf of, the Licensor for
the purpose of discussing and improving the Work, but excluding communication
that is conspicuously marked or otherwise designated in writing by the copyright
owner as "Not a Contribution."
"Contributor" shall mean Licensor and any individual or Legal Entity on behalf
of whom a Contribution has been received by Licensor and subsequently
incorporated within the Work.
2. Grant of Copyright License.
Subject to the terms and conditions of this License, each Contributor hereby
grants to You a perpetual, worldwide, non-exclusive, no-charge, royalty-free,
irrevocable copyright license to reproduce, prepare Derivative Works of,
publicly display, publicly perform, sublicense, and distribute the Work and such
Derivative Works in Source or Object form.
3. Grant of Patent License.
Subject to the terms and conditions of this License, each Contributor hereby
grants to You a perpetual, worldwide, non-exclusive, no-charge, royalty-free,
irrevocable (except as stated in this section) patent license to make, have
made, use, offer to sell, sell, import, and otherwise transfer the Work, where
such license applies only to those patent claims licensable by such Contributor
that are necessarily infringed by their Contribution(s) alone or by combination
of their Contribution(s) with the Work to which such Contribution(s) was
submitted. If You institute patent litigation against any entity (including a
cross-claim or counterclaim in a lawsuit) alleging that the Work or a
Contribution incorporated within the Work constitutes direct or contributory
patent infringement, then any patent licenses granted to You under this License
for that Work shall terminate as of the date such litigation is filed.
4. Redistribution.
You may reproduce and distribute copies of the Work or Derivative Works thereof
in any medium, with or without modifications, and in Source or Object form,
provided that You meet the following conditions:
You must give any other recipients of the Work or Derivative Works a copy of
this License; and
You must cause any modified files to carry prominent notices stating that You
changed the files; and
You must retain, in the Source form of any Derivative Works that You distribute,
all copyright, patent, trademark, and attribution notices from the Source form
of the Work, excluding those notices that do not pertain to any part of the
Derivative Works; and
If the Work includes a "NOTICE" text file as part of its distribution, then any
Derivative Works that You distribute must include a readable copy of the
attribution notices contained within such NOTICE file, excluding those notices
that do not pertain to any part of the Derivative Works, in at least one of the
following places: within a NOTICE text file distributed as part of the
Derivative Works; within the Source form or documentation, if provided along
with the Derivative Works; or, within a display generated by the Derivative
Works, if and wherever such third-party notices normally appear. The contents of
the NOTICE file are for informational purposes only and do not modify the
License. You may add Your own attribution notices within Derivative Works that
You distribute, alongside or as an addendum to the NOTICE text from the Work,
provided that such additional attribution notices cannot be construed as
modifying the License.
You may add Your own copyright statement to Your modifications and may provide
additional or different license terms and conditions for use, reproduction, or
distribution of Your modifications, or for any such Derivative Works as a whole,
provided Your use, reproduction, and distribution of the Work otherwise complies
with the conditions stated in this License.
5. Submission of Contributions.
Unless You explicitly state otherwise, any Contribution intentionally submitted
for inclusion in the Work by You to the Licensor shall be under the terms and
conditions of this License, without any additional terms or conditions.
Notwithstanding the above, nothing herein shall supersede or modify the terms of
any separate license agreement you may have executed with Licensor regarding
such Contributions.
6. Trademarks.
This License does not grant permission to use the trade names, trademarks,
service marks, or product names of the Licensor, except as required for
reasonable and customary use in describing the origin of the Work and
reproducing the content of the NOTICE file.
7. Disclaimer of Warranty.
Unless required by applicable law or agreed to in writing, Licensor provides the
Work (and each Contributor provides its Contributions) on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied,
including, without limitation, any warranties or conditions of TITLE,
NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A PARTICULAR PURPOSE. You are
solely responsible for determining the appropriateness of using or
redistributing the Work and assume any risks associated with Your exercise of
permissions under this License.
8. Limitation of Liability.
In no event and under no legal theory, whether in tort (including negligence),
contract, or otherwise, unless required by applicable law (such as deliberate
and grossly negligent acts) or agreed to in writing, shall any Contributor be
liable to You for damages, including any direct, indirect, special, incidental,
or consequential damages of any character arising as a result of this License or
out of the use or inability to use the Work (including but not limited to
damages for loss of goodwill, work stoppage, computer failure or malfunction, or
any and all other commercial damages or losses), even if such Contributor has
been advised of the possibility of such damages.
9. Accepting Warranty or Additional Liability.
While redistributing the Work or Derivative Works thereof, You may choose to
offer, and charge a fee for, acceptance of support, warranty, indemnity, or
other liability obligations and/or rights consistent with this License. However,
in accepting such obligations, You may act only on Your own behalf and on Your
sole responsibility, not on behalf of any other Contributor, and only if You
agree to indemnify, defend, and hold each Contributor harmless for any liability
incurred by, or claims asserted against, such Contributor by reason of your
accepting any such warranty or additional liability.

44
README.md Normal file
View File

@ -0,0 +1,44 @@
# I2C EEPROM Driver
Block device driver for I2C based EEPROM devices such as the 24LC or AT24C series of devices.
EEPROM devices support much higher read/write cycles than flash based memory, at a cost in terms of size. Additionally, I2C EEPROM devices support byte-level read/writes with buffering of around 32bytes during writes.
**Note:** The I2C convention for EEPROM devices does not support inspection of the memory layout of the device, so the size must be specified during construction of the driver.
More info on EEPROM can be found on wikipedia:
https://en.wikipedia.org/wiki/EEPROM
``` cpp
// Here's an example using a 24LC256 on a GR PEACH
#include "mbed.h"
#include "I2CEEBlockDevice.h"
// Create EEPROM device on I2C bus with 32kbytes of memory
I2CEEBlockDevice i2cee(D14, D15, 0xa0, 32*1024);
int main() {
printf("i2cee test\n");
// Initialize the device and print the memory layout
i2cee.init();
printf("i2cee size: %llu\n", i2cee.size());
printf("i2cee read size: %llu\n", i2cee.get_read_size());
printf("i2cee program size: %llu\n", i2cee.get_program_size());
printf("i2cee erase size: %llu\n", i2cee.get_erase_size());
// Write "Hello World!" to the first block
uint8_t *buffer = malloc(i2cee.get_erase_size());
sprintf(buffer, "Hello World!\n");
i2cee.erase(0, i2cee.get_erase_size());
i2cee.program(buffer, 0, i2cee.get_erase_size());
// Read back what was stored
i2cee.read(buffer, 0, i2cee.get_erase_size());
printf("%s", buffer);
// Deinitialize the device
i2cee.deinit();
}
```

145
TESTS/block_device/i2cee/main.cpp Normal file
View File

@ -0,0 +1,145 @@
#include "mbed.h"
#include "greentea-client/test_env.h"
#include "unity.h"
#include "utest.h"
#include "I2CEEBlockDevice.h"
#include <stdlib.h>
using namespace utest::v1;
//#if !I2CEE_INSTALLED
//#error [NOT_SUPPORTED] I2CEE Required
//#endif
#define TEST_PINS D14, D15
#define TEST_ADDR 0xa0
#define TEST_SIZE 32*1024
#define TEST_BLOCK_SIZE 64
#define TEST_FREQ 400000
#define TEST_BLOCK_COUNT 10
#define TEST_ERROR_MASK 16
const struct {
const char *name;
bd_size_t (BlockDevice::*method)();
} ATTRS[] = {
{"read size", &BlockDevice::get_read_size},
{"program size", &BlockDevice::get_program_size},
{"erase size", &BlockDevice::get_erase_size},
{"total size", &BlockDevice::size},
};
void test_read_write() {
I2CEEBlockDevice bd(TEST_PINS, TEST_ADDR,
TEST_SIZE, TEST_BLOCK_SIZE, TEST_FREQ);
int err = bd.init();
TEST_ASSERT_EQUAL(0, err);
for (unsigned a = 0; a < sizeof(ATTRS)/sizeof(ATTRS[0]); a++) {
static const char *prefixes[] = {"", "k", "M", "G"};
for (int i = 3; i >= 0; i--) {
bd_size_t size = (bd.*ATTRS[a].method)();
if (size >= (1ULL << 10*i)) {
printf("%s: %llu%sbytes (%llubytes)\n",
ATTRS[a].name, size >> 10*i, prefixes[i], size);
break;
}
}
}
bd_size_t block_size = bd.get_erase_size();
uint8_t *write_block = new uint8_t[block_size];
uint8_t *read_block = new uint8_t[block_size];
uint8_t *error_mask = new uint8_t[TEST_ERROR_MASK];
unsigned addrwidth = ceil(log(bd.size()-1) / log(16))+1;
for (int b = 0; b < TEST_BLOCK_COUNT; b++) {
// Find a random block
bd_addr_t block = (rand()*block_size) % bd.size();
// Use next random number as temporary seed to keep
// the address progressing in the pseudorandom sequence
unsigned seed = rand();
// Fill with random sequence
srand(seed);
for (bd_size_t i = 0; i < block_size; i++) {
write_block[i] = 0xff & rand();
}
// Write, sync, and read the block
printf("test %0*llx:%llu...\n", addrwidth, block, block_size);
err = bd.write(write_block, block, block_size);
TEST_ASSERT_EQUAL(0, err);
printf("write %0*llx:%llu ", addrwidth, block, block_size);
for (int i = 0; i < block_size && i < 16; i++) {
printf("%02x", write_block[i]);
}
if (block_size > 16) {
printf("...\n");
}
printf("\n");
err = bd.read(read_block, block, block_size);
TEST_ASSERT_EQUAL(0, err);
printf("read %0*llx:%llu ", addrwidth, block, block_size);
for (int i = 0; i < block_size && i < 16; i++) {
printf("%02x", read_block[i]);
}
if (block_size > 16) {
printf("...");
}
printf("\n");
// Find error mask for debugging
memset(error_mask, 0, TEST_ERROR_MASK);
bd_size_t error_scale = block_size / (TEST_ERROR_MASK*8);
srand(seed);
for (bd_size_t i = 0; i < TEST_ERROR_MASK*8; i++) {
for (bd_size_t j = 0; j < error_scale; j++) {
if ((0xff & rand()) != read_block[i*error_scale + j]) {
error_mask[i/8] |= 1 << (i%8);
}
}
}
printf("error %0*llx:%llu ", addrwidth, block, block_size);
for (int i = 0; i < TEST_ERROR_MASK; i++) {
printf("%02x", error_mask[i]);
}
printf("\n");
// Check that the data was unmodified
srand(seed);
for (bd_size_t i = 0; i < block_size; i++) {
TEST_ASSERT_EQUAL(0xff & rand(), read_block[i]);
}
}
err = bd.deinit();
TEST_ASSERT_EQUAL(0, err);
}
// Test setup
utest::v1::status_t test_setup(const size_t number_of_cases) {
GREENTEA_SETUP(30, "default_auto");
return verbose_test_setup_handler(number_of_cases);
}
Case cases[] = {
Case("Testing read write random blocks", test_read_write),
};
Specification specification(test_setup, cases);
int main() {
return !Harness::run(specification);
}