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[twi] add TWI flash write function

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stnolting 2025-03-28 22:22:36 +01:00
parent 78a8459ebe
commit 3abdfc4b00
2 changed files with 127 additions and 30 deletions
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1
sw/bootloader/hal/include/twi_flash.h
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@ -17,5 +17,6 @@
#include <stdint.h>
int twi_flash_read_word(uint32_t addr, uint32_t* rdata);
int twi_flash_write_word(uint32_t addr, uint32_t wdata);
#endif // TWI_FLASH_H

156
sw/bootloader/hal/source/twi_flash.c
View file

@ -31,20 +31,20 @@ int twi_flash_read_word(uint32_t addr, uint32_t* rdata) {
uint8_t transfer;
subwords32_t data, address;
address.uint32 = addr;
/***********************
* set address to read
***********************/
// TWI module available?
if (neorv32_twi_available() == 0) {
return 1;
}
// start condition
neorv32_twi_generate_start();
// send device address
uint8_t device_id = TWI_DEVICE_ID;
transfer = device_id << 1;
transfer = TWI_DEVICE_ID | 0; // TWI WRITE
device_nack |= neorv32_twi_transfer(&transfer, 0);
// send read access address
// send access address
address.uint32 = addr;
#if (TWI_FLASH_ADDR_BYTES == 1)
transfer = address.uint8[0];
device_nack |= neorv32_twi_transfer(&transfer, 0);
@ -73,39 +73,135 @@ int twi_flash_read_word(uint32_t addr, uint32_t* rdata) {
#error "Invalid TWI_FLASH_ADDR_BYTES configuration!"
#endif
/***********************
* read data
***********************/
// repeated-start condition
neorv32_twi_generate_start();
// send device address with read flag
transfer = device_id << 1;
transfer |= 0x01;
// send device address
transfer = TWI_DEVICE_ID | 1; // TWI READ
device_nack |= neorv32_twi_transfer(&transfer, 0);
if (device_nack) {
neorv32_twi_generate_stop();
return 1;
}
// read
for (i = 0; i < 3; i++) {
// read four bytes
for (i = 0; i < 4; i++) {
transfer = 0xFF;
neorv32_twi_transfer(&transfer, 1); // ACK by host
if (i == 3) {
device_nack |= neorv32_twi_transfer(&transfer, 1); // NACK by host
}
else {
neorv32_twi_transfer(&transfer, 0);
}
data.uint8[i] = transfer;
}
// last read with NACK by host
transfer = 0xFF;
neorv32_twi_transfer(&transfer, 0); // NACK by host
data.uint8[3] = transfer;
*rdata = data.uint32;
// send stop condition
neorv32_twi_generate_stop();
return 0;
if (device_nack) {
neorv32_uart0_puts("\nTWI_R ERR\n");
return 1;
}
else {
neorv32_uart0_puts("\nTWI_R OK\n");
return 0;
}
#else
return 1;
#endif
}
/**********************************************************************//**
* Write single byte to TWI flash.
*
* @param addr TWI flash write address.
* @param wdata TWI flash write data.
* @return 0 if success, !=0 if error
**************************************************************************/
int twi_flash_write_byte(uint32_t addr, uint8_t wdata) {
int device_nack = 0;
uint8_t transfer;
subwords32_t address;
// start condition
neorv32_twi_generate_start();
// send device address
transfer = TWI_DEVICE_ID | 0; // TWI WRITE
device_nack |= neorv32_twi_transfer(&transfer, 0);
// send read access address
address.uint32 = addr;
#if (TWI_FLASH_ADDR_BYTES == 1)
transfer = address.uint8[0];
device_nack |= neorv32_twi_transfer(&transfer, 0);
#elif (TWI_FLASH_ADDR_BYTES == 2)
transfer = address.uint8[1];
device_nack |= neorv32_twi_transfer(&transfer, 0);
transfer = address.uint8[0];
device_nack |= neorv32_twi_transfer(&transfer, 0);
#elif (TWI_FLASH_ADDR_BYTES == 3)
transfer = address.uint8[2];
device_nack |= neorv32_twi_transfer(&transfer, 0);
transfer = address.uint8[1];
device_nack |= neorv32_twi_transfer(&transfer, 0);
transfer = address.uint8[0];
device_nack |= neorv32_twi_transfer(&transfer, 0);
#elif (TWI_FLASH_ADDR_BYTES == 4)
transfer = address.uint8[3];
device_nack |= neorv32_twi_transfer(&transfer, 0);
transfer = address.uint8[2];
device_nack |= neorv32_twi_transfer(&transfer, 0);
transfer = address.uint8[1];
device_nack |= neorv32_twi_transfer(&transfer, 0);
transfer = address.uint8[0];
device_nack |= neorv32_twi_transfer(&transfer, 0);
#else
#error "Invalid TWI_FLASH_ADDR_BYTES configuration!"
#endif
// send write data
transfer = wdata;
device_nack |= neorv32_twi_transfer(&transfer, 0);
// send stop condition
neorv32_twi_generate_stop();
return device_nack;
}
/**********************************************************************//**
* Write word to TWI flash.
*
* @param addr TWI flash write address.
* @param wdata TWI flash write data.
* @return 0 if success, !=0 if error
**************************************************************************/
int twi_flash_write_word(uint32_t addr, uint32_t wdata) {
#if (TWI_EN != 0)
int device_nack = 0;
subwords32_t data;
// TWI module available?
if (neorv32_twi_available() == 0) {
return 1;
}
// write four bytes
data.uint32 = wdata;
device_nack += twi_flash_write_byte(addr+0, data.uint8[0]);
device_nack += twi_flash_write_byte(addr+1, data.uint8[1]);
device_nack += twi_flash_write_byte(addr+2, data.uint8[2]);
device_nack += twi_flash_write_byte(addr+3, data.uint8[3]);
if (device_nack) {
return 1;
}
else {
return 0;
}
#else
return 1;
#endif