Wim Huiskamp / Mbed 2 deprecated mbed_bus

Libraries and Example of mbed parallel bus using I2C port expanders

Dependencies:   HDSP253X mbed PCF8574_Bus

main.cpp@1:e180256ba6fb, 2011-09-17 (annotated)

Committer:
wim
Date:
Sat Sep 17 15:35:39 2011 +0000
Revision:
1:e180256ba6fb
Parent:
0:2467aed99127 
Example of using the parallel bus to control a smart alphanumeric display

Who changed what in which revision?

UserRevisionLine numberNew contents of line
wim 0:2467aed99127 1 /* mbed bus - Main
wim 0:2467aed99127 2 * Copyright (c) 2011 Wim Huiskamp
wim 0:2467aed99127 3 *
wim 0:2467aed99127 4 * Released under the MIT License: http://mbed.org/license/mit
wim 0:2467aed99127 5 *
wim 0:2467aed99127 6 * version 0.2 Initial Release
wim 0:2467aed99127 7 */
wim 0:2467aed99127 8 #include "mbed.h"
wim 0:2467aed99127 9 #include "BusDefines.h"
wim 0:2467aed99127 10 #include "PCF8574_DataBus.h"
wim 0:2467aed99127 11 #include "PCF8574_AddressBus.h"
wim 0:2467aed99127 12 #include "PCF8574_EnableBus.h"
wim 0:2467aed99127 13 #include "MBED_ControlBus.h"
wim 1:e180256ba6fb 14 #include "HDSP253X_Display.h"
wim 0:2467aed99127 15
wim 0:2467aed99127 16 // Debug stuff
wim 0:2467aed99127 17 #define __DEBUG
wim 0:2467aed99127 18 #include "Dbg.h"
wim 0:2467aed99127 19
wim 0:2467aed99127 20 // mbed Interface Hardware definitions
wim 0:2467aed99127 21 DigitalOut myled1(LED1);
wim 0:2467aed99127 22 DigitalOut myled2(LED2);
wim 0:2467aed99127 23 DigitalOut myled3(LED3);
wim 0:2467aed99127 24 DigitalOut heartbeatLED(LED4);
wim 0:2467aed99127 25
wim 0:2467aed99127 26 // Host PC Communication channels
wim 0:2467aed99127 27 Serial pc(USBTX, USBRX);
wim 0:2467aed99127 28
wim 0:2467aed99127 29 //I2C Bus
wim 0:2467aed99127 30 I2C i2c(D_SDA, D_SCL);
wim 0:2467aed99127 31
wim 0:2467aed99127 32 // Bus Interface Hardware definitions
wim 0:2467aed99127 33 PCF8574_DataBus databus = PCF8574_DataBus(i2c, D_I2C_DATA_BUS); //Copy constructors..
wim 0:2467aed99127 34 PCF8574_AddressBus addressbus = PCF8574_AddressBus(i2c, D_I2C_ADDR_BUS);
wim 0:2467aed99127 35 PCF8574_EnableBus enablebus = PCF8574_EnableBus(i2c, D_I2C_ENA_BUS);
wim 0:2467aed99127 36 MBED_ControlBus controlbus = MBED_ControlBus(D_WR, D_RD, D_DTR, D_CDBUF, D_CDINT);
wim 0:2467aed99127 37
wim 1:e180256ba6fb 38 // Display Hardware definitions
wim 1:e180256ba6fb 39 HDSP253X_Display LED_display = HDSP253X_Display(databus, addressbus, enablebus, controlbus);
wim 1:e180256ba6fb 40
wim 0:2467aed99127 41 // Dummy delay
wim 0:2467aed99127 42 #define DEVICE_WAIT_MS 0
wim 0:2467aed99127 43
wim 0:2467aed99127 44
wim 0:2467aed99127 45 // Variables for Heartbeat and Status monitoring
wim 0:2467aed99127 46 Ticker heartbeat;
wim 0:2467aed99127 47 bool heartbeatflag=false;
wim 0:2467aed99127 48
wim 0:2467aed99127 49 // Cycle Timer
wim 0:2467aed99127 50 Timer cycletimer;
wim 0:2467aed99127 51 int cyclecount = 0;
wim 0:2467aed99127 52 const int maxcount = 10;
wim 0:2467aed99127 53
wim 0:2467aed99127 54 // Local functions
wim 0:2467aed99127 55 void clear_screen() {
wim 0:2467aed99127 56 //ANSI Terminal Commands
wim 0:2467aed99127 57 pc.printf("\x1B[2J");
wim 0:2467aed99127 58 pc.printf("\x1B[H");
wim 0:2467aed99127 59 }
wim 0:2467aed99127 60
wim 0:2467aed99127 61
wim 0:2467aed99127 62 void init_interfaces() {
wim 0:2467aed99127 63 // Init Host PC communication, default is 9600
wim 0:2467aed99127 64 pc.baud(D_BAUDRATE);
wim 0:2467aed99127 65
wim 0:2467aed99127 66 // Init I/F hardware
wim 0:2467aed99127 67 i2c.frequency(100000);
wim 0:2467aed99127 68
wim 0:2467aed99127 69 //Done, Tell me about it
wim 0:2467aed99127 70 myled1 = 1;
wim 1:e180256ba6fb 71 // DBG("Init Interfaces Done\r");
wim 0:2467aed99127 72 }
wim 0:2467aed99127 73
wim 0:2467aed99127 74
wim 0:2467aed99127 75 // Heartbeat monitor
wim 0:2467aed99127 76 void pulse() {
wim 0:2467aed99127 77 heartbeatLED = !heartbeatLED;
wim 0:2467aed99127 78 }
wim 0:2467aed99127 79
wim 0:2467aed99127 80 void heartbeat_start() {
wim 0:2467aed99127 81 heartbeat.attach(&pulse, 0.5);
wim 0:2467aed99127 82 heartbeatflag = true;
wim 0:2467aed99127 83 }
wim 0:2467aed99127 84
wim 0:2467aed99127 85 void heartbeat_stop() {
wim 0:2467aed99127 86 heartbeat.detach();
wim 0:2467aed99127 87 heartbeatflag = false;
wim 0:2467aed99127 88 }
wim 0:2467aed99127 89
wim 0:2467aed99127 90 void show_LEDS () {
wim 0:2467aed99127 91 static int state = 0;
wim 0:2467aed99127 92
wim 0:2467aed99127 93 switch (state) {
wim 0:2467aed99127 94 case 0:
wim 0:2467aed99127 95 myled1 = 1;
wim 0:2467aed99127 96 myled2 = 0;
wim 0:2467aed99127 97 myled3 = 0;
wim 0:2467aed99127 98 state = 1;
wim 0:2467aed99127 99 break;
wim 0:2467aed99127 100 case 1:
wim 0:2467aed99127 101 myled1 = 0;
wim 0:2467aed99127 102 myled2 = 1;
wim 0:2467aed99127 103 myled3 = 0;
wim 0:2467aed99127 104 state = 2;
wim 0:2467aed99127 105 break;
wim 0:2467aed99127 106 case 2:
wim 0:2467aed99127 107 myled1 = 0;
wim 0:2467aed99127 108 myled2 = 0;
wim 0:2467aed99127 109 myled3 = 1;
wim 0:2467aed99127 110 state = 0;
wim 0:2467aed99127 111 break;
wim 0:2467aed99127 112 }
wim 0:2467aed99127 113 }
wim 0:2467aed99127 114
wim 0:2467aed99127 115
wim 0:2467aed99127 116 // The next two functions are examples of low-level reading and writing to a device that is connected on the mbed bus.
wim 0:2467aed99127 117 // In your own application you can develop a Class for each specific slave device and include modified versions of the
wim 0:2467aed99127 118 // functions below as 'private' functions. This allows you to hardcode the device CS_pin signals, define specific delays
wim 0:2467aed99127 119 // when needed, change the sequence of CS, WR etc or mask out certain address or databits when they are not used in a certain case.
wim 0:2467aed99127 120 //
wim 0:2467aed99127 121
wim 0:2467aed99127 122 /*---------------------------------------------------------------------------*\
wim 0:2467aed99127 123 |
wim 0:2467aed99127 124 | Function: write
wim 0:2467aed99127 125 |
wim 0:2467aed99127 126 | Description: Low level data write routine for device. Takes in data
wim 0:2467aed99127 127 | and address and CS pin to identify the device and writes
wim 0:2467aed99127 128 | data to the display. For simplicity, entire address byte
wim 0:2467aed99127 129 | is written, even though top two bits are unused inputs.
wim 0:2467aed99127 130 | After performing the operation, address lines are set
wim 0:2467aed99127 131 | all high, in order to eliminate current drain through
wim 0:2467aed99127 132 | pullup resistors (0.5mA per pin with 10K pullups)
wim 0:2467aed99127 133 |
wim 0:2467aed99127 134 | Parameters: address - full address in bits 0-5
wim 0:2467aed99127 135 | device - enum CS_Pin for Chip Select pin
wim 0:2467aed99127 136 | data - data byte to write out
wim 0:2467aed99127 137 |
wim 0:2467aed99127 138 | Returns: Nothing.
wim 0:2467aed99127 139 |
wim 0:2467aed99127 140 \*---------------------------------------------------------------------------*/
wim 0:2467aed99127 141
wim 0:2467aed99127 142 void write(uint8_t address, CS_Pin device, uint8_t data)
wim 0:2467aed99127 143 {
wim 0:2467aed99127 144 // // Switch databus buffer to outputs (note: this is the default state)
wim 0:2467aed99127 145 // controlbus.busdir(WRITE);
wim 0:2467aed99127 146 // // Switch databus to outputs
wim 0:2467aed99127 147 // databus.busdir(WRITE);
wim 0:2467aed99127 148
wim 0:2467aed99127 149
wim 0:2467aed99127 150 // Write out the address on to the addressbus and wait
wim 0:2467aed99127 151 addressbus.write(address);
wim 0:2467aed99127 152 wait_ms(DEVICE_WAIT_MS);
wim 0:2467aed99127 153
wim 0:2467aed99127 154 // Set CE low and wait
wim 0:2467aed99127 155 enablebus.chipselect(device, LOW);
wim 0:2467aed99127 156 wait_ms(DEVICE_WAIT_MS);
wim 0:2467aed99127 157
wim 0:2467aed99127 158 // Write data to the databus
wim 0:2467aed99127 159 databus.write(data);
wim 0:2467aed99127 160 wait_ms(DEVICE_WAIT_MS);
wim 0:2467aed99127 161
wim 0:2467aed99127 162 // Set WR low, wait, then set high and wait
wim 0:2467aed99127 163 controlbus.WR(LOW);
wim 0:2467aed99127 164 wait_ms(DEVICE_WAIT_MS);
wim 0:2467aed99127 165 controlbus.WR(HIGH);
wim 0:2467aed99127 166 wait_ms(DEVICE_WAIT_MS);
wim 0:2467aed99127 167
wim 0:2467aed99127 168 // Set CE high and wait
wim 0:2467aed99127 169 enablebus.chipselect(device, HIGH);
wim 0:2467aed99127 170 wait_ms(DEVICE_WAIT_MS);
wim 0:2467aed99127 171
wim 0:2467aed99127 172 // // Switch databus back to inputs
wim 0:2467aed99127 173 // databus.busdir(READ);
wim 0:2467aed99127 174 // // Switch databus buffer back to inputs
wim 0:2467aed99127 175 // controlbus.busdir(READ);
wim 0:2467aed99127 176
wim 0:2467aed99127 177 // // Set address lines all high to minimise power through pullups
wim 0:2467aed99127 178 // addressbus.write(0xFF);
wim 0:2467aed99127 179 }
wim 0:2467aed99127 180
wim 0:2467aed99127 181 /*---------------------------------------------------------------------------*\
wim 0:2467aed99127 182 |
wim 0:2467aed99127 183 | Function: read
wim 0:2467aed99127 184 |
wim 0:2467aed99127 185 | Description: Low level data read routine for a Device. Takes in
wim 0:2467aed99127 186 | address and CS pin to identify the device and then
wim 0:2467aed99127 187 | reads data from the device.
wim 0:2467aed99127 188 | After performing the operation, address lines are set
wim 0:2467aed99127 189 | all high, in order to eliminate current drain through
wim 0:2467aed99127 190 | pullup resistors (0.5mA per pin with 10K pullups)
wim 0:2467aed99127 191 |
wim 0:2467aed99127 192 | Parameters: address - 8 bit address
wim 0:2467aed99127 193 | device - enum CS_Pin for Chip Select pin
wim 0:2467aed99127 194 | Returns: data - data byte read
wim 0:2467aed99127 195 |
wim 0:2467aed99127 196 \*---------------------------------------------------------------------------*/
wim 0:2467aed99127 197
wim 0:2467aed99127 198 uint8_t read(uint8_t address, CS_Pin device)
wim 0:2467aed99127 199 {
wim 0:2467aed99127 200 uint8_t data = 0;
wim 0:2467aed99127 201
wim 0:2467aed99127 202 // Switch databus to inputs (default state is output)
wim 0:2467aed99127 203 databus.busdir(READ);
wim 0:2467aed99127 204 // Switch databus buffer to inputs
wim 0:2467aed99127 205 controlbus.busdir(READ);
wim 0:2467aed99127 206
wim 0:2467aed99127 207 // Write out the address on to the addressbus and wait
wim 0:2467aed99127 208 addressbus.write(address);
wim 0:2467aed99127 209 wait_ms(DEVICE_WAIT_MS);
wim 0:2467aed99127 210
wim 0:2467aed99127 211 // Set CE low and wait
wim 0:2467aed99127 212 enablebus.chipselect(device, LOW);
wim 0:2467aed99127 213 wait_ms(DEVICE_WAIT_MS);
wim 0:2467aed99127 214
wim 0:2467aed99127 215 // Set RD low and wait
wim 0:2467aed99127 216 controlbus.RD(LOW);
wim 0:2467aed99127 217 wait_ms(DEVICE_WAIT_MS);
wim 0:2467aed99127 218
wim 0:2467aed99127 219 // Read the data byte from databus
wim 0:2467aed99127 220 data = databus.read();
wim 0:2467aed99127 221
wim 0:2467aed99127 222 // set RD high and wait
wim 0:2467aed99127 223 controlbus.RD(HIGH);
wim 0:2467aed99127 224 wait_ms(DEVICE_WAIT_MS);
wim 0:2467aed99127 225
wim 0:2467aed99127 226 // Set CE high and wait
wim 0:2467aed99127 227 enablebus.chipselect(device, HIGH);
wim 0:2467aed99127 228 wait_ms(DEVICE_WAIT_MS);
wim 0:2467aed99127 229
wim 0:2467aed99127 230 // // Set address lines all high to minimise power through pullups
wim 0:2467aed99127 231 // addressbus.write(0xFF);
wim 0:2467aed99127 232
wim 0:2467aed99127 233 // Switch databus buffer back to outputs
wim 0:2467aed99127 234 controlbus.busdir(WRITE);
wim 0:2467aed99127 235 // Switch databus to outputs
wim 0:2467aed99127 236 databus.busdir(WRITE);
wim 0:2467aed99127 237
wim 0:2467aed99127 238 // Return read data to caller
wim 0:2467aed99127 239 return data;
wim 0:2467aed99127 240 }
wim 0:2467aed99127 241
wim 1:e180256ba6fb 242
wim 1:e180256ba6fb 243 void HDSP_BITE() {
wim 1:e180256ba6fb 244 int count;
wim 1:e180256ba6fb 245
wim 1:e180256ba6fb 246 for (count=0; count<5; count++) {
wim 1:e180256ba6fb 247 LED_display.locate(0);
wim 1:e180256ba6fb 248 LED_display.printf("BITE - ");
wim 1:e180256ba6fb 249 wait(0.05);
wim 1:e180256ba6fb 250 LED_display.locate(0);
wim 1:e180256ba6fb 251 LED_display.printf("BITE \\ ");
wim 1:e180256ba6fb 252 wait(0.05);
wim 1:e180256ba6fb 253 LED_display.locate(0);
wim 1:e180256ba6fb 254 LED_display.printf("BITE | ");
wim 1:e180256ba6fb 255 wait(0.05);
wim 1:e180256ba6fb 256 LED_display.locate(0);
wim 1:e180256ba6fb 257 LED_display.printf("BITE / ");
wim 1:e180256ba6fb 258 wait(0.05);
wim 1:e180256ba6fb 259 LED_display.locate(0);
wim 1:e180256ba6fb 260 LED_display.printf("BITE - ");
wim 1:e180256ba6fb 261 wait(0.05);
wim 1:e180256ba6fb 262 };
wim 1:e180256ba6fb 263
wim 1:e180256ba6fb 264 LED_display.locate(0);
wim 1:e180256ba6fb 265 LED_display.printf("BITE OK");
wim 1:e180256ba6fb 266
wim 1:e180256ba6fb 267 LED_display.set_blink_mode(true);
wim 1:e180256ba6fb 268 wait(2.0);
wim 1:e180256ba6fb 269 LED_display.set_blink_mode(false);
wim 1:e180256ba6fb 270
wim 1:e180256ba6fb 271 LED_display.cls();
wim 1:e180256ba6fb 272
wim 1:e180256ba6fb 273 //Done, Tell me about it
wim 1:e180256ba6fb 274 // DBG("BITE Done, Main, Step = %d\r", 30);
wim 1:e180256ba6fb 275 }
wim 1:e180256ba6fb 276
wim 1:e180256ba6fb 277 void HDSP_Init_UDC() {
wim 1:e180256ba6fb 278
wim 1:e180256ba6fb 279 // batt empty
wim 1:e180256ba6fb 280 LED_display.define_user_char(0, 0x0E, 0x11, 0x11, 0x11, 0x11, 0x11, 0x1F);
wim 1:e180256ba6fb 281 // batt full
wim 1:e180256ba6fb 282 LED_display.define_user_char(1, 0x0E, 0x1F, 0x1F, 0x1F, 0x1F, 0x1F, 0x1F);
wim 1:e180256ba6fb 283 }
wim 1:e180256ba6fb 284
wim 1:e180256ba6fb 285
wim 1:e180256ba6fb 286 void HDSP_Show_UDC() {
wim 1:e180256ba6fb 287
wim 1:e180256ba6fb 288 LED_display.locate(0);
wim 1:e180256ba6fb 289 LED_display.printf("Batt ");
wim 1:e180256ba6fb 290 // LED_display.putc(HDSP253X_ASCII_UDC_CHARS + 0);
wim 1:e180256ba6fb 291 // LED_display.putc(HDSP253X_ASCII_UDC_CHARS + 1);
wim 1:e180256ba6fb 292 LED_display.putudc(0);
wim 1:e180256ba6fb 293 LED_display.putudc(1);
wim 1:e180256ba6fb 294
wim 1:e180256ba6fb 295 wait(2.0);
wim 1:e180256ba6fb 296 }
wim 1:e180256ba6fb 297
wim 0:2467aed99127 298 int main() {
wim 0:2467aed99127 299 int address, result;
wim 0:2467aed99127 300 uint8_t data, dummy;
wim 0:2467aed99127 301
wim 0:2467aed99127 302 init_interfaces();
wim 0:2467aed99127 303
wim 0:2467aed99127 304 heartbeat_start();
wim 0:2467aed99127 305
wim 0:2467aed99127 306 clear_screen();
wim 1:e180256ba6fb 307
wim 1:e180256ba6fb 308 HDSP_Init_UDC();
wim 1:e180256ba6fb 309
wim 1:e180256ba6fb 310 // DBG("Start Main Loop\r");
wim 0:2467aed99127 311
wim 0:2467aed99127 312 //Testing stuff
wim 0:2467aed99127 313
wim 0:2467aed99127 314 //Test cycletime
wim 0:2467aed99127 315 cycletimer.start();
wim 0:2467aed99127 316 cycletimer.reset();
wim 1:e180256ba6fb 317
wim 1:e180256ba6fb 318
wim 1:e180256ba6fb 319 #if (0)
wim 1:e180256ba6fb 320 // Bus test
wim 0:2467aed99127 321 while (1) {
wim 0:2467aed99127 322 for (address=0; address<256; address++) {
wim 0:2467aed99127 323 //data = read(address, CS_SWITCH);
wim 0:2467aed99127 324
wim 0:2467aed99127 325 dummy = ~address;
wim 0:2467aed99127 326 write(address, LATCHEN_1, dummy);
wim 0:2467aed99127 327 // wait(0.05);
wim 0:2467aed99127 328 }
wim 0:2467aed99127 329
wim 0:2467aed99127 330 // Just for Info, lets see how fast this cycle is...
wim 0:2467aed99127 331 cyclecount++;
wim 0:2467aed99127 332 if (cyclecount == maxcount) {
wim 0:2467aed99127 333 pc.printf("Freq = %d Hz\r", (cyclecount * 256 * 1000) / cycletimer.read_ms());
wim 0:2467aed99127 334 cyclecount = 0;
wim 0:2467aed99127 335 cycletimer.reset();
wim 0:2467aed99127 336 }
wim 0:2467aed99127 337
wim 0:2467aed99127 338 show_LEDS ();
wim 0:2467aed99127 339 }
wim 1:e180256ba6fb 340 #else
wim 1:e180256ba6fb 341 // LED Display test
wim 1:e180256ba6fb 342 while (1) {
wim 1:e180256ba6fb 343 HDSP_BITE();
wim 0:2467aed99127 344
wim 1:e180256ba6fb 345 cyclecount++;
wim 1:e180256ba6fb 346 if (cyclecount == 10) {
wim 1:e180256ba6fb 347 cyclecount = 0;
wim 1:e180256ba6fb 348 // LED_display.printf ("Restart ");
wim 1:e180256ba6fb 349 HDSP_Show_UDC();
wim 1:e180256ba6fb 350 }
wim 1:e180256ba6fb 351 else {
wim 1:e180256ba6fb 352 LED_display.printf ("Cnt= %2d", cyclecount);
wim 1:e180256ba6fb 353 }
wim 1:e180256ba6fb 354 wait(2.0);
wim 1:e180256ba6fb 355 pc.printf (".");
wim 1:e180256ba6fb 356
wim 1:e180256ba6fb 357 show_LEDS ();
wim 1:e180256ba6fb 358 }
wim 1:e180256ba6fb 359
wim 1:e180256ba6fb 360 #endif
wim 0:2467aed99127 361
wim 0:2467aed99127 362 DBG("I'll be back...\r\r");
wim 0:2467aed99127 363 }