From a98070f21288fae025c6ffa2e08b775fb661bb4b Mon Sep 17 00:00:00 2001 From: Ryan Date: Tue, 21 Jan 2025 09:53:35 +1100 Subject: [PATCH] [Docs] Correct I2C API reference (#24840) --- docs/drivers/i2c.md | 34 +++++++++++++++++++--------------- 1 file changed, 19 insertions(+), 15 deletions(-) diff --git a/docs/drivers/i2c.md b/docs/drivers/i2c.md index c806a090c56..2ef7afccc9d 100644 --- a/docs/drivers/i2c.md +++ b/docs/drivers/i2c.md @@ -147,7 +147,7 @@ void i2c_init(void) { --- -### `i2c_status_t i2c_transmit(uint8_t address, uint8_t *data, uint16_t length, uint16_t timeout)` {#api-i2c-transmit} +### `i2c_status_t i2c_transmit(uint8_t address, const uint8_t* data, uint16_t length, uint16_t timeout)` {#api-i2c-transmit} Send multiple bytes to the selected I2C device. @@ -155,7 +155,7 @@ Send multiple bytes to the selected I2C device. - `uint8_t address` The 7-bit I2C address of the device. - - `uint8_t *data` + - `const uint8_t* data` A pointer to the data to transmit. - `uint16_t length` The number of bytes to write. Take care not to overrun the length of `data`. @@ -176,7 +176,7 @@ Receive multiple bytes from the selected I2C device. - `uint8_t address` The 7-bit I2C address of the device. - - `uint8_t *data` + - `uint8_t* data` A pointer to the buffer to read into. - `uint16_t length` The number of bytes to read. Take care not to overrun the length of `data`. @@ -189,7 +189,7 @@ Receive multiple bytes from the selected I2C device. --- -### `i2c_status_t i2c_write_register(uint8_t devaddr, uint8_t regaddr, uint8_t* data, uint16_t length, uint16_t timeout)` {#api-i2c-write-register} +### `i2c_status_t i2c_write_register(uint8_t devaddr, uint8_t regaddr, const uint8_t* data, uint16_t length, uint16_t timeout)` {#api-i2c-write-register} Writes to a register with an 8-bit address on the I2C device. @@ -199,7 +199,7 @@ Writes to a register with an 8-bit address on the I2C device. The 7-bit I2C address of the device. - `uint8_t regaddr` The register address to write to. - - `uint8_t *data` + - `const uint8_t* data` A pointer to the data to transmit. - `uint16_t length` The number of bytes to write. Take care not to overrun the length of `data`. @@ -212,7 +212,7 @@ Writes to a register with an 8-bit address on the I2C device. --- -### `i2c_status_t i2c_write_register16(uint8_t devaddr, uint16_t regaddr, uint8_t* data, uint16_t length, uint16_t timeout)` {#api-i2c-write-register16} +### `i2c_status_t i2c_write_register16(uint8_t devaddr, uint16_t regaddr, const uint8_t* data, uint16_t length, uint16_t timeout)` {#api-i2c-write-register16} Writes to a register with a 16-bit address (big endian) on the I2C device. @@ -222,10 +222,10 @@ Writes to a register with a 16-bit address (big endian) on the I2C device. The 7-bit I2C address of the device. - `uint16_t regaddr` The register address to write to. - - `uint8_t *data` + - `const uint8_t* data` A pointer to the data to transmit. - `uint16_t length` - The number of bytes to write. Take care not to overrun the length of `data`. + The number of bytes to write. Take care not to overrun the length of `data`. - `uint16_t timeout` The time in milliseconds to wait for a response from the target device. @@ -245,8 +245,10 @@ Reads from a register with an 8-bit address on the I2C device. The 7-bit I2C address of the device. - `uint8_t regaddr` The register address to read from. + - `uint8_t data` + A pointer to a buffer to read into. - `uint16_t length` - The number of bytes to read. Take care not to overrun the length of `data`. + The number of bytes to read. Take care not to overrun the length of `data`. - `uint16_t timeout` The time in milliseconds to wait for a response from the target device. @@ -266,8 +268,10 @@ Reads from a register with a 16-bit address (big endian) on the I2C device. The 7-bit I2C address of the device. - `uint16_t regaddr` The register address to read from. + - `uint8_t* data` + A pointer to a buffer to read into. - `uint16_t length` - The number of bytes to read. Take care not to overrun the length of `data`. + The number of bytes to read. Take care not to overrun the length of `data`. - `uint16_t timeout` The time in milliseconds to wait for a response from the target device. @@ -279,19 +283,19 @@ Reads from a register with a 16-bit address (big endian) on the I2C device. ### `i2c_status_t i2c_ping_address(uint8_t address, uint16_t timeout)` {#api-i2c-ping-address} -Pings the I2C bus for a specific address. +Pings the I2C bus for a specific address. -On ChibiOS a "best effort" attempt is made by reading a single byte from register 0 at the requested address. This should generally work except for I2C devices that do not not respond to a register 0 read request, which will result in a false negative result (unsucessful response to ping attempt). +On ChibiOS a "best effort" attempt is made by reading a single byte from register 0 at the requested address. This should generally work except for I2C devices that do not not respond to a register 0 read request, which will result in a false negative result (unsuccessful response to ping attempt). -This function is weakly defined, meaning it can be overridden if necessary for your particular use case: +This function is weakly defined, meaning it can be overridden if necessary for your particular use case. -#### Arguments +#### Arguments {#api-i2c-ping-address-arguments} - `uint8_t address` The 7-bit I2C address of the device (ie. without the read/write bit - this will be set automatically). - `uint16_t timeout` The time in milliseconds to wait for a response from the target device. -#### Return Value +#### Return Value {#api-i2c-ping-address-return} `I2C_STATUS_TIMEOUT` if the timeout period elapses, `I2C_STATUS_ERROR` if some other error occurs, otherwise `I2C_STATUS_SUCCESS`.