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1 ingob 1
/*#######################################################################################*/
2
/* !!! THIS IS NOT FREE SOFTWARE !!!                                                     */
3
/*#######################################################################################*/
4
// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
5
// + Copyright (c) 2008 Ingo Busker, Holger Buss
171 ingob 6
// + Nur für den privaten Gebrauch / NON-COMMERCIAL USE ONLY
1 ingob 7
// + FOR NON COMMERCIAL USE ONLY
8
// + www.MikroKopter.com
9
// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
37 killagreg 10
// + Es gilt für das gesamte Projekt (Hardware, Software, Binärfiles, Sourcecode und Dokumentation),
11
// + dass eine Nutzung (auch auszugsweise) nur für den privaten (nicht-kommerziellen) Gebrauch zulässig ist.
12
// + Sollten direkte oder indirekte kommerzielle Absichten verfolgt werden, ist mit uns (info@mikrokopter.de) Kontakt
13
// + bzgl. der Nutzungsbedingungen aufzunehmen.
1 ingob 14
// + Eine kommerzielle Nutzung ist z.B.Verkauf von MikroKoptern, Bestückung und Verkauf von Platinen oder Bausätzen,
15
// + Verkauf von Luftbildaufnahmen, usw.
16
// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
37 killagreg 17
// + Werden Teile des Quellcodes (mit oder ohne Modifikation) weiterverwendet oder veröffentlicht,
1 ingob 18
// + unterliegen sie auch diesen Nutzungsbedingungen und diese Nutzungsbedingungen incl. Copyright müssen dann beiliegen
19
// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
20
// + Sollte die Software (auch auszugesweise) oder sonstige Informationen des MikroKopter-Projekts
21
// + auf anderen Webseiten oder sonstigen Medien veröffentlicht werden, muss unsere Webseite "http://www.mikrokopter.de"
22
// + eindeutig als Ursprung verlinkt werden
23
// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
24
// + Keine Gewähr auf Fehlerfreiheit, Vollständigkeit oder Funktion
25
// + Benutzung auf eigene Gefahr
26
// + Wir übernehmen keinerlei Haftung für direkte oder indirekte Personen- oder Sachschäden
27
// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
171 ingob 28
// + Die Portierung oder Nutzung der Software (oder Teile davon) auf andere Systeme (ausser der Hardware von www.mikrokopter.de) ist nur
1 ingob 29
// + mit unserer Zustimmung zulässig
30
// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
31
// + Die Funktion printf_P() unterliegt ihrer eigenen Lizenz und ist hiervon nicht betroffen
32
// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
37 killagreg 33
// + Redistributions of source code (with or without modifications) must retain the above copyright notice,
1 ingob 34
// + this list of conditions and the following disclaimer.
35
// +   * Neither the name of the copyright holders nor the names of contributors may be used to endorse or promote products derived
36
// +     from this software without specific prior written permission.
37 killagreg 37
// +   * The use of this project (hardware, software, binary files, sources and documentation) is only permitted
1 ingob 38
// +     for non-commercial use (directly or indirectly)
37 killagreg 39
// +     Commercial use (for excample: selling of MikroKopters, selling of PCBs, assembly, ...) is only permitted
1 ingob 40
// +     with our written permission
37 killagreg 41
// +   * If sources or documentations are redistributet on other webpages, out webpage (http://www.MikroKopter.de) must be
42
// +     clearly linked as origin
171 ingob 43
// +   * porting the sources to other systems or using the software on other systems (except hardware from www.mikrokopter.de) is not allowed
1 ingob 44
//
45
// +  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
46
// +  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
47
// +  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
48
// +  ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
49
// +  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
50
// +  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
51
// +  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
52
// +  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
53
// +  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
54
// +  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
37 killagreg 55
// +  POSSIBILITY OF SUCH DAMAGE.
1 ingob 56
// ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
41 ingob 57
#include <string.h>
58
#include "91x_lib.h"
59
#include "i2c.h"
60
#include "uart1.h"
119 killagreg 61
#include "timer1.h"
136 killagreg 62
#include "config.h"
41 ingob 63
#include "led.h"
1 ingob 64
 
248 killagreg 65
 
241 killagreg 66
volatile u8 I2C_State = I2C_STATE_OFF; // only one byte, because of sync by nesting irqs
1 ingob 67
 
248 killagreg 68
// number of bytes to send
69
volatile u8 I2C_TxBufferSize;
70
// number of bytes to receive
41 ingob 71
volatile u8 I2C_RxBufferSize;
248 killagreg 72
// the transfer buffer
73
volatile u8 I2C_Buffer[I2C_BUFFER_LEN];
74
// the transfer direction 
41 ingob 75
volatile u8 I2C_Direction;
248 killagreg 76
// the slave address
241 killagreg 77
volatile u8 I2C_SlaveAddress = 0x00;
248 killagreg 78
// function pointer to process the received bytes
241 killagreg 79
I2C_pRxHandler_t I2C_pRxHandler = NULL;
248 killagreg 80
// goblal timeout 
41 ingob 81
volatile u32 I2C1_Timeout = 0;
1 ingob 82
 
83
//--------------------------------------------------------------
84
void I2C1_Init(void)
85
{
41 ingob 86
        I2C_InitTypeDef   I2C_Struct;
87
        GPIO_InitTypeDef  GPIO_InitStructure;
149 killagreg 88
 
241 killagreg 89
        I2C_State = I2C_STATE_OFF;
37 killagreg 90
 
110 killagreg 91
        UART1_PutString("\r\n I2C init...");
41 ingob 92
        // enable Port 2 peripherie
93
        SCU_APBPeriphClockConfig(__GPIO2, ENABLE);
94
        // disable a reset state
95
        SCU_APBPeriphReset(__GPIO2, DISABLE);
1 ingob 96
 
41 ingob 97
        // free a busy bus
1 ingob 98
 
41 ingob 99
        // At switch on I2C devices can get in a state where they
100
        // are still waiting for a command due to all the bus lines bouncing
101
        // around at startup have started clocking data into the device(s).
102
        // Enable the ports as open collector port outputs
103
        // and clock out at least 9 SCL pulses, then generate a stop
104
        // condition and then leave the clock line high.
37 killagreg 105
 
41 ingob 106
        // configure P2.2->I2C1_CLKOUT and P2.3->I2C1_DOUT to normal port operation
107
        GPIO_StructInit(&GPIO_InitStructure);
108
        GPIO_InitStructure.GPIO_Direction = GPIO_PinOutput;
109
        GPIO_InitStructure.GPIO_Pin = GPIO_Pin_2 | GPIO_Pin_3;
110
        GPIO_InitStructure.GPIO_Type = GPIO_Type_OpenCollector;
196 killagreg 111
        GPIO_InitStructure.GPIO_IPInputConnected = GPIO_IPInputConnected_Disable;
41 ingob 112
        GPIO_InitStructure.GPIO_Alternate = GPIO_OutputAlt1;
113
        GPIO_Init(GPIO2, &GPIO_InitStructure);
37 killagreg 114
 
41 ingob 115
        u8 i;
116
        u32 delay;
117
        // set SCL high and then SDA to low (start condition)
118
        GPIO_WriteBit(GPIO2, GPIO_Pin_2, Bit_SET);
119
        delay = SetDelay(1);
120
        while (!CheckDelay(delay));
121
        GPIO_WriteBit(GPIO2, GPIO_Pin_3, Bit_RESET);
122
        // toggle SCL at least 10 times from high to low to high
123
        for(i = 0; i < 10; i++)
124
        {
125
                delay = SetDelay(1);
126
                while (!CheckDelay(delay));
1 ingob 127
 
41 ingob 128
                GPIO_WriteBit(GPIO2, GPIO_Pin_2, Bit_RESET);
129
                delay = SetDelay(1);
130
                while (!CheckDelay(delay));
131
                GPIO_WriteBit(GPIO2, GPIO_Pin_2, Bit_SET);
132
        }
133
        delay = SetDelay(1);
134
        while (!CheckDelay(delay));
135
        // create stop condition setting SDA HIGH when SCL is HIGH
136
        GPIO_WriteBit(GPIO2, GPIO_Pin_3, Bit_SET);
37 killagreg 137
 
138
 
41 ingob 139
        // reconfigure P2.2->I2C1_CLKOUT and P2.3->I2C1_DOUT
140
        GPIO_StructInit(&GPIO_InitStructure);
141
        GPIO_InitStructure.GPIO_Direction = GPIO_PinOutput;
142
        GPIO_InitStructure.GPIO_Pin = GPIO_Pin_2 | GPIO_Pin_3;
143
        GPIO_InitStructure.GPIO_Type = GPIO_Type_OpenCollector;
196 killagreg 144
        GPIO_InitStructure.GPIO_IPInputConnected = GPIO_IPInputConnected_Enable;
41 ingob 145
        GPIO_InitStructure.GPIO_Alternate = GPIO_OutputAlt2; //I2C1_CLKOUT, I2C1_DOUT
146
        GPIO_Init(GPIO2, &GPIO_InitStructure);
147
 
148
        // enable I2C peripherie
149
        SCU_APBPeriphClockConfig(__I2C1,ENABLE);
150
        // reset I2C peripherie
151
        SCU_APBPeriphReset(__I2C1,ENABLE);
152
        SCU_APBPeriphReset(__I2C1,DISABLE);
153
 
154
        I2C_DeInit(I2C1);
155
        I2C_StructInit(&I2C_Struct);
156
        I2C_Struct.I2C_GeneralCall = I2C_GeneralCall_Disable;
157
        I2C_Struct.I2C_Ack = I2C_Ack_Enable;
136 killagreg 158
        I2C_Struct.I2C_CLKSpeed = I2C1_CLOCK;
41 ingob 159
        I2C_Struct.I2C_OwnAddress = 0x00;
160
        I2C_Init(I2C1, &I2C_Struct);
161
 
248 killagreg 162
        // empty rx and tx buffer counters
41 ingob 163
        I2C_TxBufferSize = 0;
164
        I2C_RxBufferSize = 0;
165
 
166
        I2C_Cmd(I2C1, ENABLE);
167
        I2C_ITConfig(I2C1, ENABLE);
168
 
136 killagreg 169
        VIC_Config(I2C1_ITLine, VIC_IRQ , PRIORITY_I2C1);
41 ingob 170
 
189 killagreg 171
        I2C1_Timeout = SetDelay(10*I2C1_TIMEOUT);
41 ingob 172
        I2C_GenerateSTOP(I2C1, ENABLE);
241 killagreg 173
        I2C_State = I2C_STATE_IDLE;
41 ingob 174
 
248 killagreg 175
        // start some dummy transmissions cycles
176
        // to get the irq routine to work
177
        for(i=0;i<10;i++)
178
        {
179
                I2C_State = I2C_STATE_BUFFBUSY;
180
                I2C_Transmission(0,1,0,1);
181
                if(I2C_WaitForEndOfTransmission(10)) break;
182
                UART1_Putchar('.');
183
        }
110 killagreg 184
        UART1_PutString("ok");
1 ingob 185
}
186
 
41 ingob 187
 
1 ingob 188
//--------------------------------------------------------------
41 ingob 189
void I2C1_Deinit(void)
1 ingob 190
{
79 killagreg 191
        GPIO_InitTypeDef  GPIO_InitStructure;
110 killagreg 192
        UART1_PutString("\r\n I2C deinit...");
41 ingob 193
        I2C_GenerateStart(I2C1, DISABLE);
194
        I2C_GenerateSTOP(I2C1, ENABLE);
195
        VIC_ITCmd(I2C1_ITLine, DISABLE);
241 killagreg 196
        I2C_State = I2C_STATE_OFF;
41 ingob 197
        I2C_ITConfig(I2C1, DISABLE);
198
        I2C_Cmd(I2C1, DISABLE);
199
        I2C_DeInit(I2C1);
200
        SCU_APBPeriphClockConfig(__I2C1, DISABLE);
79 killagreg 201
 
41 ingob 202
        // set ports to input
203
        SCU_APBPeriphClockConfig(__GPIO2, ENABLE);
204
        GPIO_StructInit(&GPIO_InitStructure);
205
        GPIO_InitStructure.GPIO_Direction =     GPIO_PinInput;
79 killagreg 206
        GPIO_InitStructure.GPIO_Pin =                   GPIO_Pin_2 | GPIO_Pin_3;
207
        GPIO_InitStructure.GPIO_Type =                  GPIO_Type_PushPull;
196 killagreg 208
        GPIO_InitStructure.GPIO_IPInputConnected =      GPIO_IPInputConnected_Disable;
79 killagreg 209
        GPIO_InitStructure.GPIO_Alternate =     GPIO_InputAlt1;
210
        GPIO_Init(GPIO2, &GPIO_InitStructure);
1 ingob 211
 
241 killagreg 212
        // empty rx and tx buffer
41 ingob 213
        I2C_TxBufferSize = 0;
214
        I2C_RxBufferSize = 0;
37 killagreg 215
 
189 killagreg 216
        I2C1_Timeout = SetDelay(10*I2C1_TIMEOUT);
37 killagreg 217
 
110 killagreg 218
        UART1_PutString("ok");
41 ingob 219
}
1 ingob 220
 
41 ingob 221
//--------------------------------------------------------------
222
void I2C1_IRQHandler(void)
223
{
241 killagreg 224
        static u8 Rx_Idx = 0, Tx_Idx = 0;
41 ingob 225
        u16 status;
189 killagreg 226
 
195 killagreg 227
        //IENABLE;  // do not enable IRQ nesting for I2C!!!!
41 ingob 228
        // detemine I2C State
229
        status = I2C_GetLastEvent(I2C1);
230
 
231
        if(status & (I2C_FLAG_AF|I2C_FLAG_BERR))  // if an acknowledge failure or bus error occured
79 killagreg 232
        {       // Set and subsequently clear the STOP bit while BTF is set.
41 ingob 233
                while(I2C_GetFlagStatus (I2C1, I2C_FLAG_BTF) != RESET)
234
                {
189 killagreg 235
                        I2C_GenerateSTOP (I2C1, ENABLE);  // free the bus
41 ingob 236
                        I2C_GenerateSTOP (I2C1, DISABLE); // free the bus
237
                }
241 killagreg 238
                I2C_State = I2C_STATE_IDLE;
189 killagreg 239
                VIC_ITCmd(I2C1_ITLine, DISABLE);
41 ingob 240
                LED_GRN_OFF;
189 killagreg 241
                return;
41 ingob 242
        }
243
        else
244
        {       // depending on current i2c state
241 killagreg 245
                switch(status)
41 ingob 246
                {
247
                        // the start condition was initiated on the bus
248
                        case I2C_EVENT_MASTER_MODE_SELECT:
249
                                LED_GRN_ON;
250
                                // update current bus state variable
241 killagreg 251
                                // jump to rx state if there is nothing to send
41 ingob 252
                                switch(I2C_Direction)
253
                                {
254
                                        case I2C_MODE_TRANSMITTER:
241 killagreg 255
                                                I2C_State = I2C_STATE_TX_PROGRESS;
41 ingob 256
                                                break;
79 killagreg 257
 
41 ingob 258
                                        case I2C_MODE_RECEIVER:
248 killagreg 259
                                                if (I2C_RxBufferSize == 0) // nothing to send?
41 ingob 260
                                                {
261
                                                        I2C_GenerateSTOP (I2C1, ENABLE);
189 killagreg 262
                                                        VIC_ITCmd(I2C1_ITLine, DISABLE);
263
                                                        LED_GRN_OFF;
241 killagreg 264
                                                        I2C_State = I2C_STATE_IDLE;
41 ingob 265
                                                        return;
266
                                                }
267
                                                else
268
                                                {
241 killagreg 269
                                                        I2C_State = I2C_STATE_RX_PROGRESS;
41 ingob 270
                                                }
271
                                                break;
79 killagreg 272
 
41 ingob 273
                                        default: // invalid direction
274
                                                I2C_GenerateSTOP (I2C1, ENABLE);
189 killagreg 275
                                                VIC_ITCmd(I2C1_ITLine, DISABLE);
276
                                                LED_GRN_OFF;
241 killagreg 277
                                                I2C_State = I2C_STATE_IDLE;
41 ingob 278
                                                return;
279
                                }
280
                                // enable acknowledge
281
                                I2C_AcknowledgeConfig (I2C1, ENABLE);
282
                                // send address/direction byte on the bus
241 killagreg 283
                                I2C_Send7bitAddress(I2C1, I2C_SlaveAddress, I2C_Direction);
41 ingob 284
                                break;
79 killagreg 285
 
41 ingob 286
                        // the address byte was send
287
                        case I2C_EVENT_MASTER_MODE_SELECTED:
288
                                // Clear EV6 by set again the PE bit
79 killagreg 289
                                I2C_Cmd(I2C1, ENABLE);
41 ingob 290
                                switch(I2C_State)
291
                                {
241 killagreg 292
                                        case I2C_STATE_TX_PROGRESS:
293
                                        // send 1st data byte
41 ingob 294
                                        Tx_Idx = 0;
248 killagreg 295
                                        I2C_SendData(I2C1, I2C_Buffer[Tx_Idx]);
241 killagreg 296
                                        Tx_Idx++;
41 ingob 297
                                        // reset timeout
189 killagreg 298
                                        I2C1_Timeout = SetDelay(I2C1_TIMEOUT); // after inactivity the I2C1 bus will be reset
41 ingob 299
                                        break;
79 killagreg 300
 
241 killagreg 301
                                        case I2C_STATE_RX_PROGRESS:
41 ingob 302
                                        Rx_Idx = 0;
241 killagreg 303
                                        // disable acknoledge if only one byte has to be read
304
                                        if(I2C_RxBufferSize == 1) I2C_AcknowledgeConfig (I2C1, DISABLE);               
41 ingob 305
                                        break;
79 killagreg 306
 
41 ingob 307
                                        default: // unknown I2C state
308
                                        // should never happen
309
                                        I2C_GenerateSTOP (I2C1, ENABLE);
189 killagreg 310
                                        LED_GRN_OFF;
311
                                        VIC_ITCmd(I2C1_ITLine, DISABLE);
241 killagreg 312
                                        I2C_State = I2C_STATE_IDLE;
189 killagreg 313
                                        return;
41 ingob 314
                                        break;
315
                                }
316
                                break;
79 killagreg 317
 
41 ingob 318
                        // the master has transmitted a byte and slave has been acknowledged
319
                        case I2C_EVENT_MASTER_BYTE_TRANSMITTED:
79 killagreg 320
 
41 ingob 321
                                // some bytes have to be transmitted
322
                                if(Tx_Idx < I2C_TxBufferSize)
323
                                {
248 killagreg 324
                                        I2C_SendData(I2C1, I2C_Buffer[Tx_Idx]);
241 killagreg 325
                                        Tx_Idx++;
41 ingob 326
                                }
189 killagreg 327
                                else // last byte was send
328
                                {
41 ingob 329
                                        // generate stop or repeated start condition
241 killagreg 330
                                        if (I2C_RxBufferSize > 0) // is any answer byte expected?
41 ingob 331
                                        {
79 killagreg 332
                                                I2C_Direction = I2C_MODE_RECEIVER; // switch to master receiver after repeated start condition
333
                                                I2C_GenerateStart(I2C1, ENABLE);   // initiate repeated start condition on the bus
41 ingob 334
                                        }
335
                                        else
336
                                        {   // stop communication
337
                                                I2C_GenerateSTOP(I2C1, ENABLE); // generate stop condition to free the bus
189 killagreg 338
                                                VIC_ITCmd(I2C1_ITLine, DISABLE);
41 ingob 339
                                                LED_GRN_OFF;
241 killagreg 340
                                                I2C_State = I2C_STATE_IDLE;                     // ready for new actions        
41 ingob 341
                                        }
342
                                }
343
                                break;
79 killagreg 344
 
41 ingob 345
                        // the master has received a byte from the slave
79 killagreg 346
                        case I2C_EVENT_MASTER_BYTE_RECEIVED:
41 ingob 347
                                // some bytes have to be received
241 killagreg 348
                                if ( Rx_Idx+1 < I2C_RxBufferSize)
41 ingob 349
                                {       // copy received byte  from the data register to the rx-buffer
248 killagreg 350
                                        I2C_Buffer[Rx_Idx] = I2C_ReceiveData(I2C1);
41 ingob 351
                                }
241 killagreg 352
                                else // if the last byte was received
41 ingob 353
                                {
354
                                        // generate a STOP condition on the bus before reading data register
355
                                        I2C_GenerateSTOP(I2C1, ENABLE);
248 killagreg 356
                                        I2C_Buffer[Rx_Idx] = I2C_ReceiveData(I2C1);
241 killagreg 357
                                        // call the rx handler function to process recieved data
248 killagreg 358
                                        if(I2C_pRxHandler != NULL) (*I2C_pRxHandler)((u8*)I2C_Buffer, I2C_RxBufferSize);
241 killagreg 359
                                        I2C1_Timeout = SetDelay(I2C1_TIMEOUT);
360
                                        DebugOut.Analog[15]++;
189 killagreg 361
                                        VIC_ITCmd(I2C1_ITLine, DISABLE);
362
                                        LED_GRN_OFF;
241 killagreg 363
                                        I2C_State = I2C_STATE_IDLE;
189 killagreg 364
                                        return;
41 ingob 365
                                }
366
                                Rx_Idx++;
367
                                // if the 2nd last byte was received disable acknowledge for the last one
241 killagreg 368
                                if ( (Rx_Idx + 1) == I2C_RxBufferSize )
41 ingob 369
                                {
241 killagreg 370
                                        I2C_AcknowledgeConfig(I2C1, DISABLE);
41 ingob 371
                                }
372
                                break;
79 killagreg 373
 
241 killagreg 374
                        default:// unknown event
375
                                // should never happen
376
                                I2C_GenerateSTOP (I2C1, ENABLE);
377
                                LED_GRN_OFF;
378
                                VIC_ITCmd(I2C1_ITLine, DISABLE);
379
                                I2C_State = I2C_STATE_IDLE;
41 ingob 380
                                break;
381
                }
382
        }
195 killagreg 383
        //IDISABLE;      // do not enable IRQ nesting for I2C!!!!
1 ingob 384
}
248 killagreg 385
 
241 killagreg 386
// ----------------------------------------------------------------------------------------
248 killagreg 387
// wait for end of transmission
388
u8 I2C_WaitForEndOfTransmission(u32 timeout)
389
{
390
        u32 time = SetDelay(timeout);
391
        while(I2C_State != I2C_STATE_IDLE)
392
        {
393
                if(CheckDelay(time)) return(0);
394
        }
395
        return(1);
396
}
397
 
398
// ----------------------------------------------------------------------------------------
399
// try to get access to the transfer buffer      within a timeout limit
400
// returs 1 on success and 0 on error/timeout
401
u8 I2C_LockBuffer(u32 timeout)
402
{      
403
        if(I2C_WaitForEndOfTransmission(timeout))
404
        {
405
                I2C_State = I2C_STATE_BUFFBUSY;
406
                return(1);
407
        }
408
        else return(0);
409
}
410
// ----------------------------------------------------------------------------------------
241 killagreg 411
// initate an i2c transmission
248 killagreg 412
u8 I2C_Transmission(u8 SlaveAddr, u8 TxBytes, I2C_pRxHandler_t pRxHandler, u8 RxBytes)
1 ingob 413
{
241 killagreg 414
        u8 retval = 0;
248 killagreg 415
        if(I2C_State == I2C_STATE_BUFFBUSY)
416
        {
417
                if((RxBytes > I2C_BUFFER_LEN) || (TxBytes > I2C_BUFFER_LEN))
418
                {
419
                        I2C_State = I2C_STATE_IDLE;
420
                        return(retval);
421
                }      
241 killagreg 422
                I2C_RxBufferSize = RxBytes;
248 killagreg 423
                I2C_TxBufferSize = TxBytes;
241 killagreg 424
                // set direction to master transmitter
248 killagreg 425
                if( (I2C_TxBufferSize > 0) && (I2C_TxBufferSize < I2C_BUFFER_LEN) ) I2C_Direction = I2C_MODE_TRANSMITTER;
426
                else if (( I2C_RxBufferSize > 0 ) && (I2C_RxBufferSize < I2C_BUFFER_LEN) ) I2C_Direction = I2C_MODE_RECEIVER;
241 killagreg 427
                else // nothing to send or receive
189 killagreg 428
                {
248 killagreg 429
                        I2C_State = I2C_STATE_IDLE;
241 killagreg 430
                        I2C_TxBufferSize = 0;
431
                        I2C_RxBufferSize = 0;
432
                        return(retval);
189 killagreg 433
                }
241 killagreg 434
                // update slave address and rx data handler     funbction pointer
435
                I2C_SlaveAddress = SlaveAddr;
436
                I2C_pRxHandler = pRxHandler;
189 killagreg 437
                // test on busy flag and clear it
438
                I2C_CheckEvent( I2C1, I2C_FLAG_BUSY );
242 killagreg 439
                // enable I2C IRQ
440
                VIC_ITCmd(I2C1_ITLine, ENABLE);
189 killagreg 441
                // initiate start condition on the bus
442
                I2C_GenerateStart(I2C1, ENABLE);
241 killagreg 443
                retval = 1;
444
         }
445
         return(retval);
41 ingob 446
}