From 17f6b83057f60aae39ed0124f8015fc4c8d578b6 Mon Sep 17 00:00:00 2001 From: aleph Date: Thu, 6 Jan 2005 16:09:40 +0000 Subject: [PATCH] Split twi/eeprom functions from eeprom module in separate twi module git-svn-id: https://src.develer.com/svnoss/bertos/trunk@329 38d2e660-2303-0410-9eaa-f027e97ec537 --- drv/eeprom.c | 215 +++-------------------------------------------- drv/twi.c | 233 +++++++++++++++++++++++++++++++++++++++++++++++++++ drv/twi.h | 34 ++++++++ 3 files changed, 279 insertions(+), 203 deletions(-) create mode 100755 drv/twi.c create mode 100755 drv/twi.h diff --git a/drv/eeprom.c b/drv/eeprom.c index 57861376..b7238335 100755 --- a/drv/eeprom.c +++ b/drv/eeprom.c @@ -16,6 +16,9 @@ /*#* *#* $Log$ + *#* Revision 1.15 2005/01/06 16:09:40 aleph + *#* Split twi/eeprom functions from eeprom module in separate twi module + *#* *#* Revision 1.14 2004/12/13 12:07:06 bernie *#* DISABLE_IRQSAVE/ENABLE_IRQRESTORE: Convert to IRQ_SAVE_DISABLE/IRQ_RESTORE. *#* @@ -62,17 +65,15 @@ #include "eeprom.h" -#include -#include /* cpu_to_be16() */ #include -#include -#include // IRQ_SAVE_DISABLE(), IRQ_RESTORE() #include // CONFIG_EEPROM_VERIFY #include // MIN() +#include +#include +#include // cpu_to_be16() #include // memset() -#include // Configuration sanity checks #if !defined(CONFIG_EEPROM_VERIFY) || (CONFIG_EEPROM_VERIFY != 0 && CONFIG_EEPROM_VERIFY != 1) @@ -80,172 +81,6 @@ #endif -/* Wait for TWINT flag set: bus is ready */ -#define WAIT_TWI_READY do {} while (!(TWCR & BV(TWINT))) - -/*! \name EEPROM control codes */ -/*@{*/ -#define SLA_W 0xA0 -#define SLA_R 0xA1 -/*@}*/ - - -/*! - * Send START condition on the bus. - * - * \return true on success, false otherwise. - */ -static bool twi_start(void) -{ - TWCR = BV(TWINT) | BV(TWSTA) | BV(TWEN); - WAIT_TWI_READY; - - if (TW_STATUS == TW_START || TW_STATUS == TW_REP_START) - return true; - - DB(kprintf("!TW_(REP)START: %x\n", TWSR);) - return false; -} - - -/*! - * Send START condition and select slave for write. - * - * \return true on success, false otherwise. - */ -static bool twi_start_w(uint8_t slave_addr) -{ - ASSERT(slave_addr < 8); - - /* - * Loop on the select write sequence: when the eeprom is busy - * writing previously sent data it will reply to the SLA_W - * control byte with a NACK. In this case, we must - * keep trying until the eeprom responds with an ACK. - */ - while (twi_start()) - { - TWDR = SLA_W | (slave_addr << 1); - TWCR = BV(TWINT) | BV(TWEN); - WAIT_TWI_READY; - - if (TW_STATUS == TW_MT_SLA_ACK) - return true; - else if (TW_STATUS != TW_MT_SLA_NACK) - { - DB(kprintf("!TW_MT_SLA_(N)ACK: %x\n", TWSR);) - break; - } - } - - return false; -} - - -/*! - * Send START condition and select slave for read. - * - * \return true on success, false otherwise. - */ -static bool twi_start_r(uint8_t slave_addr) -{ - ASSERT(slave_addr < 8); - - if (twi_start()) - { - TWDR = SLA_R | (slave_addr << 1); - TWCR = BV(TWINT) | BV(TWEN); - WAIT_TWI_READY; - - if (TW_STATUS == TW_MR_SLA_ACK) - return true; - - DB(kprintf("!TW_MR_SLA_ACK: %x\n", TWSR);) - } - - return false; -} - - -/*! - * Send STOP condition. - */ -static void twi_stop(void) -{ - TWCR = BV(TWINT) | BV(TWEN) | BV(TWSTO); -} - - -/*! - * Send a sequence of bytes in master transmitter mode - * to the selected slave device through the TWI bus. - * - * \return true on success, false on error. - */ -static bool twi_send(const void *_buf, size_t count) -{ - const uint8_t *buf = (const uint8_t *)_buf; - - while (count--) - { - TWDR = *buf++; - TWCR = BV(TWINT) | BV(TWEN); - WAIT_TWI_READY; - if (TW_STATUS != TW_MT_DATA_ACK) - { - DB(kprintf("!TW_MT_DATA_ACK: %x\n", TWSR);) - return false; - } - } - - return true; -} - - -/*! - * Receive a sequence of one or more bytes from the - * selected slave device in master receive mode through - * the TWI bus. - * - * Received data is placed in \c buf. - * - * \return true on success, false on error - */ -static bool twi_recv(void *_buf, size_t count) -{ - uint8_t *buf = (uint8_t *)_buf; - - /* - * When reading the last byte the TWEA bit is not - * set, and the eeprom should answer with NACK - */ - while (count--) - { - TWCR = BV(TWINT) | BV(TWEN) | (count ? BV(TWEA) : 0); - WAIT_TWI_READY; - - if (count) - { - if (TW_STATUS != TW_MR_DATA_ACK) - { - DB(kprintf("!TW_MR_DATA_ACK: %x\n", TWSR);) - return false; - } - } - else - { - if (TW_STATUS != TW_MR_DATA_NACK) - { - DB(kprintf("!TW_MR_DATA_NACK: %x\n", TWSR);) - return false; - } - } - *buf++ = TWDR; - } - - return true; -} - /*! * Copy \c count bytes from buffer \c buf to * eeprom at address \c addr. @@ -473,38 +308,7 @@ void eeprom_erase(e2addr_t addr, size_t count) */ void eeprom_init(void) { - cpuflags_t flags; - IRQ_SAVE_DISABLE(flags); - - /* - * This is pretty useless according to AVR's datasheet, - * but it helps us driving the TWI data lines on boards - * where the bus pull-up resistors are missing. This is - * probably due to some unwanted interaction between the - * port pin and the TWI lines. - */ -#if defined(__AVR_ATmega64__) - PORTD |= BV(PD0) | BV(PD1); - DDRD |= BV(PD0) | BV(PD1); -#elif defined(__AVR_ATmega8__) - PORTC |= BV(PC4) | BV(PC5); - DDRC |= BV(PC4) | BV(PC5); -#else - #error Unsupported architecture -#endif - - /* - * Set speed: - * F = CLOCK_FREQ / (16 + 2*TWBR * 4^TWPS) - */ - #define TWI_FREQ 100000 /* ~100 kHz */ - #define TWI_PRESC 1 /* 4 ^ TWPS */ - - TWBR = (CLOCK_FREQ / (2 * TWI_FREQ * TWI_PRESC)) - (8 / TWI_PRESC); - TWSR = 0; - TWCR = BV(TWEN); - - IRQ_RESTORE(flags); + twi_init(); } @@ -520,11 +324,15 @@ void eeprom_test(void) // Write something to EEPROM using unaligned sequential writes for (i = 0; i < 42; ++i) + { + wdt_reset(); eeprom_write(i * sizeof magic, magic, sizeof magic); + } // Read back with single-byte reads for (i = 0; i < 42 * sizeof magic; ++i) { + wdt_reset(); eeprom_read(i, buf, 1); kprintf("EEPROM byte read: %c (%d)\n", buf[0], buf[0]); ASSERT(buf[0] == magic[i % sizeof magic]); @@ -533,6 +341,7 @@ void eeprom_test(void) // Read back again using sequential reads for (i = 0; i < 42; ++i) { + wdt_reset(); memset(buf, 0, sizeof buf); eeprom_read(i * sizeof magic, buf, sizeof magic); kprintf("EEPROM seq read @ 0x%x: '%s'\n", i * sizeof magic, buf); diff --git a/drv/twi.c b/drv/twi.c new file mode 100755 index 00000000..ff52b68a --- /dev/null +++ b/drv/twi.c @@ -0,0 +1,233 @@ +/*! + * \file + * + * + * \brief Driver for the AVR ATMega TWI (implementation) + * + * \version $Id$ + * + * \author Stefano Fedrigo + * \author Bernardo Innocenti + */ + +/*#* + *#* $Log$ + *#* Revision 1.1 2005/01/06 16:09:40 aleph + *#* Split twi/eeprom functions from eeprom module in separate twi module + *#* + *#*/ + +#include "twi.h" +#include "config.h" +#include +#include +#include + +#include + + +/* Wait for TWINT flag set: bus is ready */ +#define WAIT_TWI_READY do {} while (!(TWCR & BV(TWINT))) + +/*! \name EEPROM control codes */ +/*@{*/ +#define SLA_W 0xA0 +#define SLA_R 0xA1 +/*@}*/ + + +/*! + * Send START condition on the bus. + * + * \return true on success, false otherwise. + */ +static bool twi_start(void) +{ + TWCR = BV(TWINT) | BV(TWSTA) | BV(TWEN); + WAIT_TWI_READY; + + if (TW_STATUS == TW_START || TW_STATUS == TW_REP_START) + return true; + + kprintf("!TW_(REP)START: %x\n", TWSR); + return false; +} + + +/*! + * Send START condition and select slave for write. + * + * \return true on success, false otherwise. + */ +bool twi_start_w(uint8_t slave_addr) +{ + ASSERT(slave_addr < 8); + + /* + * Loop on the select write sequence: when the eeprom is busy + * writing previously sent data it will reply to the SLA_W + * control byte with a NACK. In this case, we must + * keep trying until the eeprom responds with an ACK. + */ + while (twi_start()) + { + TWDR = SLA_W | (slave_addr << 1); + TWCR = BV(TWINT) | BV(TWEN); + WAIT_TWI_READY; + + if (TW_STATUS == TW_MT_SLA_ACK) + return true; + else if (TW_STATUS != TW_MT_SLA_NACK) + { + kprintf("!TW_MT_SLA_(N)ACK: %x\n", TWSR); + break; + } + } + + return false; +} + + +/*! + * Send START condition and select slave for read. + * + * \return true on success, false otherwise. + */ +bool twi_start_r(uint8_t slave_addr) +{ + ASSERT(slave_addr < 8); + + if (twi_start()) + { + TWDR = SLA_R | (slave_addr << 1); + TWCR = BV(TWINT) | BV(TWEN); + WAIT_TWI_READY; + + if (TW_STATUS == TW_MR_SLA_ACK) + return true; + + kprintf("!TW_MR_SLA_ACK: %x\n", TWSR); + } + + return false; +} + + +/*! + * Send STOP condition. + */ +void twi_stop(void) +{ + TWCR = BV(TWINT) | BV(TWEN) | BV(TWSTO); +} + + +/*! + * Send a sequence of bytes in master transmitter mode + * to the selected slave device through the TWI bus. + * + * \return true on success, false on error. + */ +bool twi_send(const void *_buf, size_t count) +{ + const uint8_t *buf = (const uint8_t *)_buf; + + while (count--) + { + TWDR = *buf++; + TWCR = BV(TWINT) | BV(TWEN); + WAIT_TWI_READY; + if (TW_STATUS != TW_MT_DATA_ACK) + { + kprintf("!TW_MT_DATA_ACK: %x\n", TWSR); + return false; + } + } + + return true; +} + + +/*! + * Receive a sequence of one or more bytes from the + * selected slave device in master receive mode through + * the TWI bus. + * + * Received data is placed in \c buf. + * + * \return true on success, false on error + */ +bool twi_recv(void *_buf, size_t count) +{ + uint8_t *buf = (uint8_t *)_buf; + + /* + * When reading the last byte the TWEA bit is not + * set, and the eeprom should answer with NACK + */ + while (count--) + { + TWCR = BV(TWINT) | BV(TWEN) | (count ? BV(TWEA) : 0); + WAIT_TWI_READY; + + if (count) + { + if (TW_STATUS != TW_MR_DATA_ACK) + { + kprintf("!TW_MR_DATA_ACK: %x\n", TWSR); + return false; + } + } + else + { + if (TW_STATUS != TW_MR_DATA_NACK) + { + kprintf("!TW_MR_DATA_NACK: %x\n", TWSR); + return false; + } + } + *buf++ = TWDR; + } + + return true; +} + + +/*! + * Initialize TWI module. + */ +void twi_init(void) +{ + ATOMIC( + /* + * This is pretty useless according to AVR's datasheet, + * but it helps us driving the TWI data lines on boards + * where the bus pull-up resistors are missing. This is + * probably due to some unwanted interaction between the + * port pin and the TWI lines. + */ +#if defined(__AVR_ATmega64__) + PORTD |= BV(PD0) | BV(PD1); + DDRD |= BV(PD0) | BV(PD1); +#elif defined(__AVR_ATmega8__) + PORTC |= BV(PC4) | BV(PC5); + DDRC |= BV(PC4) | BV(PC5); +#else + #error Unsupported architecture +#endif + + /* + * Set speed: + * F = CLOCK_FREQ / (16 + 2*TWBR * 4^TWPS) + */ + #define TWI_FREQ 300000L /* ~300 kHz */ + #define TWI_PRESC 1 /* 4 ^ TWPS */ + + TWBR = (CLOCK_FREQ / (2 * TWI_FREQ * TWI_PRESC)) - (8 / TWI_PRESC); + TWSR = 0; + TWCR = BV(TWEN); + ); +} diff --git a/drv/twi.h b/drv/twi.h new file mode 100755 index 00000000..90564234 --- /dev/null +++ b/drv/twi.h @@ -0,0 +1,34 @@ +/*! + * \file + * + * + * \version $Id$ + * + * \author Stefano Fedrigo + * \author Bernardo Innocenti + * + * \brief Driver for the AVR ATMega TWI (interface) + */ + +/*#* + *#* $Log$ + *#* Revision 1.1 2005/01/06 16:09:40 aleph + *#* Split twi/eeprom functions from eeprom module in separate twi module + *#* + *#*/ +#ifndef DRV_TWI_H +#define DRV_TWI_H + +#include + +bool twi_start_w(uint8_t slave_addr); +bool twi_start_r(uint8_t slave_addr); +void twi_stop(void); +bool twi_send(const void *_buf, size_t count); +bool twi_recv(void *_buf, size_t count); +void twi_init(void); + +#endif /* DRV_EEPROM_H */ -- 2.25.1