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[/] [neorv32/] [trunk/] [sw/] [lib/] [source/] [neorv32_twi.c] - Blame information for rev 68

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// #################################################################################################
// # << NEORV32: neorv32_twi.c - Two-Wire Interface Controller (TWI) HW Driver >>                  #
// # ********************************************************************************************* #
// # BSD 3-Clause License                                                                          #
// #                                                                                               #
// # Copyright (c) 2021, Stephan Nolting. All rights reserved.                                     #
// #                                                                                               #
// # Redistribution and use in source and binary forms, with or without modification, are          #
// # permitted provided that the following conditions are met:                                     #
// #                                                                                               #
// # 1. Redistributions of source code must retain the above copyright notice, this list of        #
// #    conditions and the following disclaimer.                                                   #
// #                                                                                               #
// # 2. Redistributions in binary form must reproduce the above copyright notice, this list of     #
// #    conditions and the following disclaimer in the documentation and/or other materials        #
// #    provided with the distribution.                                                            #
// #                                                                                               #
// # 3. Neither the name of the copyright holder nor the names of its contributors may be used to  #
// #    endorse or promote products derived from this software without specific prior written      #
// #    permission.                                                                                #
// #                                                                                               #
// # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS   #
// # OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF               #
// # MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE    #
// # COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,     #
// # EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE #
// # GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED    #
// # AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING     #
// # NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED  #
// # OF THE POSSIBILITY OF SUCH DAMAGE.                                                            #
// # ********************************************************************************************* #
// # The NEORV32 Processor - https://github.com/stnolting/neorv32              (c) Stephan Nolting #
// #################################################################################################
 
 
/**********************************************************************//**
 * @file neorv32_twi.c
 * @author Stephan Nolting
 * @brief Two-Wire Interface Controller (TWI) HW driver source file.
 *
 * @note These functions should only be used if the TWI unit was synthesized (IO_TWI_EN = true).
 **************************************************************************/
 
#include "neorv32.h"
#include "neorv32_twi.h"
 
 
/**********************************************************************//**
 * Check if TWI unit was synthesized.
 *
 * @return 0 if TWI was not synthesized, 1 if TWI is available.
 **************************************************************************/
int neorv32_twi_available(void) {
 
  if (NEORV32_SYSINFO.SOC & (1 << SYSINFO_SOC_IO_TWI)) {
    return 1;
  }
  else {
    return 0;
  }
}
 
 
/**********************************************************************//**
 * Enable and configure TWI controller. The TWI control register bits are listed in #NEORV32_TWI_CTRL_enum.
 *
 * @param[in] prsc Clock prescaler select (0..7). See #NEORV32_CLOCK_PRSC_enum.
 **************************************************************************/
void neorv32_twi_setup(uint8_t prsc) {
 
  NEORV32_TWI.CTRL = 0; // reset
 
  uint32_t ct_enable = 1;
  ct_enable = ct_enable << TWI_CTRL_EN;
 
  uint32_t ct_prsc = (uint32_t)(prsc & 0x07);
  ct_prsc = ct_prsc << TWI_CTRL_PRSC0;
 
  NEORV32_TWI.CTRL = ct_enable | ct_prsc;
}
 
 
/**********************************************************************//**
 * Disable TWI controller.
 **************************************************************************/
void neorv32_twi_disable(void) {
 
  NEORV32_TWI.CTRL &= ~((uint32_t)(1 << TWI_CTRL_EN));
}
 
 
/**********************************************************************//**
 * Enable TWI controller.
 **************************************************************************/
void neorv32_twi_enable(void) {
 
  NEORV32_TWI.CTRL |= (uint32_t)(1 << TWI_CTRL_EN);
}
 
 
/**********************************************************************//**
 * Activate sending ACKs by controller (MACK).
 **************************************************************************/
void neorv32_twi_mack_enable(void) {
 
  NEORV32_TWI.CTRL |= ((uint32_t)(1 << TWI_CTRL_MACK));
}
 
 
/**********************************************************************//**
 * Deacivate sending ACKs by controller (MACK).
 **************************************************************************/
void neorv32_twi_mack_disable(void) {
 
  NEORV32_TWI.CTRL &= ~((uint32_t)(1 << TWI_CTRL_MACK));
}
 
 
/**********************************************************************//**
 * Check if TWI is busy.
 *
 * @note This function is blocking.
 *
 * @return 0 if idle, 1 if busy
 **************************************************************************/
int neorv32_twi_busy(void) {
 
  if (NEORV32_TWI.CTRL & (1 << TWI_CTRL_BUSY)) {
    return 1;
  }
  return 0;
}
 
 
 /**********************************************************************//**
 * Generate START condition and send first byte (address including R/W bit).
 *
 * @note Blocking function.
 *
 * @param[in] a Data byte including 7-bit address and R/W-bit (lsb).
 * @return 0: ACK received, 1: NACK received.
 **************************************************************************/
int neorv32_twi_start_trans(uint8_t a) {
 
  neorv32_twi_generate_start(); // generate START condition
 
  NEORV32_TWI.DATA = (uint32_t)a; // send address
  while(NEORV32_TWI.CTRL & (1 << TWI_CTRL_BUSY)); // wait until idle again
 
  // check for ACK/NACK
  if (NEORV32_TWI.CTRL & (1 << TWI_CTRL_ACK))
    return 0; // ACK received
  else
    return 1; // NACK received
}
 
 
 /**********************************************************************//**
 * Send data byte and also receive data byte (can be read via neorv32_twi_get_data()).
 *
 * @note Blocking function.
 *
 * @param[in] d Data byte to be send.
 * @return 0: ACK received, 1: NACK received.
 **************************************************************************/
int neorv32_twi_trans(uint8_t d) {
 
  NEORV32_TWI.DATA = (uint32_t)d; // send data
  while(NEORV32_TWI.CTRL & (1 << TWI_CTRL_BUSY)); // wait until idle again
 
  // check for ACK/NACK
  if (NEORV32_TWI.CTRL & (1 << TWI_CTRL_ACK))
    return 0; // ACK received
  else
    return 1; // NACK received
}
 
 
 /**********************************************************************//**
 * Get received data from last transmission.
 *
 * @return 0: Last received data byte.
 **************************************************************************/
uint8_t neorv32_twi_get_data(void) {
 
  return (uint8_t)NEORV32_TWI.DATA; // get RX data from previous transmission
}
 
 
 /**********************************************************************//**
 * Generate STOP condition.
 *
 * @note Blocking function.
 **************************************************************************/
void neorv32_twi_generate_stop(void) {
 
  NEORV32_TWI.CTRL |= (uint32_t)(1 << TWI_CTRL_STOP); // generate STOP condition
  while(NEORV32_TWI.CTRL & (1 << TWI_CTRL_BUSY)); // wait until idle again
}
 
 
 /**********************************************************************//**
 * Generate START condition.
 *
 * @note Blocking function.
 **************************************************************************/
void neorv32_twi_generate_start(void) {
 
  NEORV32_TWI.CTRL |= (1 << TWI_CTRL_START); // generate START condition
  while(NEORV32_TWI.CTRL & (1 << TWI_CTRL_BUSY)); // wait until idle again
}

Line No.	Rev	Author	Line
1	2	zero_gravi	`// #################################################################################################`
2	10	zero_gravi	`// # << NEORV32: neorv32_twi.c - Two-Wire Interface Controller (TWI) HW Driver >> #`
3	2	zero_gravi	`// # ********************************************************************************************* #`
4			`// # BSD 3-Clause License #`
5			`// # #`
6	44	zero_gravi	`// # Copyright (c) 2021, Stephan Nolting. All rights reserved. #`
7	2	zero_gravi	`// # #`
8			`// # Redistribution and use in source and binary forms, with or without modification, are #`
9			`// # permitted provided that the following conditions are met: #`
10			`// # #`
11			`// # 1. Redistributions of source code must retain the above copyright notice, this list of #`
12			`// # conditions and the following disclaimer. #`
13			`// # #`
14			`// # 2. Redistributions in binary form must reproduce the above copyright notice, this list of #`
15			`// # conditions and the following disclaimer in the documentation and/or other materials #`
16			`// # provided with the distribution. #`
17			`// # #`
18			`// # 3. Neither the name of the copyright holder nor the names of its contributors may be used to #`
19			`// # endorse or promote products derived from this software without specific prior written #`
20			`// # permission. #`
21			`// # #`
22			`// # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS #`
23			`// # OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF #`
24			`// # MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE #`
25			`// # COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, #`
26			`// # EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE #`
27			`// # GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED #`
28			`// # AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING #`
29			`// # NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED #`
30			`// # OF THE POSSIBILITY OF SUCH DAMAGE. #`
31			`// # ********************************************************************************************* #`
32			`// # The NEORV32 Processor - https://github.com/stnolting/neorv32 (c) Stephan Nolting #`
33			`// #################################################################################################`
34
35
36			`/********************************************************************//`
37			`* @file neorv32_twi.c`
38			`* @author Stephan Nolting`
39	10	zero_gravi	`* @brief Two-Wire Interface Controller (TWI) HW driver source file.`
40	2	zero_gravi	`*`
41	44	zero_gravi	`* @note These functions should only be used if the TWI unit was synthesized (IO_TWI_EN = true).`
42	2	zero_gravi	`**************************************************************************/`
43
44			`#include "neorv32.h"`
45			`#include "neorv32_twi.h"`
46
47
48			`/********************************************************************//`
49			`* Check if TWI unit was synthesized.`
50			`*`
51			`* @return 0 if TWI was not synthesized, 1 if TWI is available.`
52			`**************************************************************************/`
53			`int neorv32_twi_available(void) {`
54
55	64	zero_gravi	`if (NEORV32_SYSINFO.SOC & (1 << SYSINFO_SOC_IO_TWI)) {`
56	2	zero_gravi	`return 1;`
57			`}`
58			`else {`
59			`return 0;`
60			`}`
61			`}`
62
63
64			`/********************************************************************//`
65	64	zero_gravi	`* Enable and configure TWI controller. The TWI control register bits are listed in #NEORV32_TWI_CTRL_enum.`
66	2	zero_gravi	`*`
67			`* @param[in] prsc Clock prescaler select (0..7). See #NEORV32_CLOCK_PRSC_enum.`
68			`**************************************************************************/`
69	68	zero_gravi	`void neorv32_twi_setup(uint8_t prsc) {`
70	2	zero_gravi
71	64	zero_gravi	`NEORV32_TWI.CTRL = 0; // reset`
72	2	zero_gravi
73			`uint32_t ct_enable = 1;`
74	64	zero_gravi	`ct_enable = ct_enable << TWI_CTRL_EN;`
75	2	zero_gravi
76			`uint32_t ct_prsc = (uint32_t)(prsc & 0x07);`
77	64	zero_gravi	`ct_prsc = ct_prsc << TWI_CTRL_PRSC0;`
78	2	zero_gravi
79	68	zero_gravi	`NEORV32_TWI.CTRL = ct_enable \| ct_prsc;`
80	2	zero_gravi	`}`
81
82
83			`/********************************************************************//`
84			`* Disable TWI controller.`
85			`**************************************************************************/`
86			`void neorv32_twi_disable(void) {`
87
88	64	zero_gravi	`NEORV32_TWI.CTRL &= ~((uint32_t)(1 << TWI_CTRL_EN));`
89	2	zero_gravi	`}`
90
91
92			`/********************************************************************//`
93	61	zero_gravi	`* Enable TWI controller.`
94			`**************************************************************************/`
95			`void neorv32_twi_enable(void) {`
96
97	64	zero_gravi	`NEORV32_TWI.CTRL \|= (uint32_t)(1 << TWI_CTRL_EN);`
98	61	zero_gravi	`}`
99
100
101			`/********************************************************************//`
102	10	zero_gravi	`* Activate sending ACKs by controller (MACK).`
103	2	zero_gravi	`**************************************************************************/`
104			`void neorv32_twi_mack_enable(void) {`
105
106	64	zero_gravi	`NEORV32_TWI.CTRL \|= ((uint32_t)(1 << TWI_CTRL_MACK));`
107	2	zero_gravi	`}`
108
109
110			`/********************************************************************//`
111	10	zero_gravi	`* Deacivate sending ACKs by controller (MACK).`
112	2	zero_gravi	`**************************************************************************/`
113			`void neorv32_twi_mack_disable(void) {`
114
115	64	zero_gravi	`NEORV32_TWI.CTRL &= ~((uint32_t)(1 << TWI_CTRL_MACK));`
116	2	zero_gravi	`}`
117
118
119	23	zero_gravi	`/********************************************************************//`
120			`* Check if TWI is busy.`
121			`*`
122			`* @note This function is blocking.`
123			`*`
124			`* @return 0 if idle, 1 if busy`
125			`**************************************************************************/`
126			`int neorv32_twi_busy(void) {`
127
128	64	zero_gravi	`if (NEORV32_TWI.CTRL & (1 << TWI_CTRL_BUSY)) {`
129	23	zero_gravi	`return 1;`
130			`}`
131			`return 0;`
132			`}`
133
134
135	2	zero_gravi	`/********************************************************************//`
136			`* Generate START condition and send first byte (address including R/W bit).`
137			`*`
138			`* @note Blocking function.`
139			`*`
140			`* @param[in] a Data byte including 7-bit address and R/W-bit (lsb).`
141			`* @return 0: ACK received, 1: NACK received.`
142			`**************************************************************************/`
143			`int neorv32_twi_start_trans(uint8_t a) {`
144
145			`neorv32_twi_generate_start(); // generate START condition`
146
147	64	zero_gravi	`NEORV32_TWI.DATA = (uint32_t)a; // send address`
148			`while(NEORV32_TWI.CTRL & (1 << TWI_CTRL_BUSY)); // wait until idle again`
149	2	zero_gravi
150			`// check for ACK/NACK`
151	64	zero_gravi	`if (NEORV32_TWI.CTRL & (1 << TWI_CTRL_ACK))`
152	2	zero_gravi	`return 0; // ACK received`
153			`else`
154			`return 1; // NACK received`
155			`}`
156
157
158			`/********************************************************************//`
159			`* Send data byte and also receive data byte (can be read via neorv32_twi_get_data()).`
160			`*`
161			`* @note Blocking function.`
162			`*`
163			`* @param[in] d Data byte to be send.`
164			`* @return 0: ACK received, 1: NACK received.`
165			`**************************************************************************/`
166			`int neorv32_twi_trans(uint8_t d) {`
167
168	64	zero_gravi	`NEORV32_TWI.DATA = (uint32_t)d; // send data`
169			`while(NEORV32_TWI.CTRL & (1 << TWI_CTRL_BUSY)); // wait until idle again`
170	2	zero_gravi
171			`// check for ACK/NACK`
172	64	zero_gravi	`if (NEORV32_TWI.CTRL & (1 << TWI_CTRL_ACK))`
173	2	zero_gravi	`return 0; // ACK received`
174			`else`
175			`return 1; // NACK received`
176			`}`
177
178
179			`/********************************************************************//`
180			`* Get received data from last transmission.`
181			`*`
182			`* @return 0: Last received data byte.`
183			`**************************************************************************/`
184			`uint8_t neorv32_twi_get_data(void) {`
185
186	64	zero_gravi	`return (uint8_t)NEORV32_TWI.DATA; // get RX data from previous transmission`
187	2	zero_gravi	`}`
188
189
190			`/********************************************************************//`
191			`* Generate STOP condition.`
192			`*`
193			`* @note Blocking function.`
194			`**************************************************************************/`
195			`void neorv32_twi_generate_stop(void) {`
196
197	64	zero_gravi	`NEORV32_TWI.CTRL \|= (uint32_t)(1 << TWI_CTRL_STOP); // generate STOP condition`
198			`while(NEORV32_TWI.CTRL & (1 << TWI_CTRL_BUSY)); // wait until idle again`
199	2	zero_gravi	`}`
200
201
202			`/********************************************************************//`
203			`* Generate START condition.`
204			`*`
205			`* @note Blocking function.`
206			`**************************************************************************/`
207			`void neorv32_twi_generate_start(void) {`
208
209	64	zero_gravi	`NEORV32_TWI.CTRL \|= (1 << TWI_CTRL_START); // generate START condition`
210			`while(NEORV32_TWI.CTRL & (1 << TWI_CTRL_BUSY)); // wait until idle again`
211	2	zero_gravi	`}`

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[/] [neorv32/] [trunk/] [sw/] [lib/] [source/] [neorv32_twi.c] - Blame information for rev 68