2 comedi/drivers/mpc624.c
3 Hardware driver for a Micro/sys inc. MPC-624 PC/104 board
5 COMEDI - Linux Control and Measurement Device Interface
6 Copyright (C) 2000 David A. Schleef <ds@schleef.org>
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 2 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program; if not, write to the Free Software
20 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
25 Description: Micro/sys MPC-624 PC/104 board
26 Devices: [Micro/sys] MPC-624 (mpc624)
27 Author: Stanislaw Raczynski <sraczynski@op.pl>
28 Updated: Thu, 15 Sep 2005 12:01:18 +0200
31 The Micro/sys MPC-624 board is based on the LTC2440 24-bit sigma-delta
34 Subdevices supported by the driver:
35 - Analog In: supported
36 - Digital I/O: not supported
38 - EEPROM: not supported
40 Configuration Options:
41 [0] - I/O base address
43 Convertion rate RMS noise Effective Number Of Bits
59 #include "../comedidev.h"
61 #include <linux/ioport.h>
62 #include <linux/delay.h>
64 /* Consecutive I/O port addresses */
65 #define MPC624_SIZE 16
67 /* Offsets of different ports */
68 #define MPC624_MASTER_CONTROL 0 /* not used */
69 #define MPC624_GNMUXCH 1 /* Gain, Mux, Channel of ADC */
70 #define MPC624_ADC 2 /* read/write to/from ADC */
71 #define MPC624_EE 3 /* read/write to/from serial EEPROM via I2C */
72 #define MPC624_LEDS 4 /* write to LEDs */
73 #define MPC624_DIO 5 /* read/write to/from digital I/O ports */
74 #define MPC624_IRQ_MASK 6 /* IRQ masking enable/disable */
76 /* Register bits' names */
77 #define MPC624_ADBUSY (1<<5)
78 #define MPC624_ADSDO (1<<4)
79 #define MPC624_ADFO (1<<3)
80 #define MPC624_ADCS (1<<2)
81 #define MPC624_ADSCK (1<<1)
82 #define MPC624_ADSDI (1<<0)
84 /* SDI Speed/Resolution Programming bits */
85 #define MPC624_OSR4 (1<<31)
86 #define MPC624_OSR3 (1<<30)
87 #define MPC624_OSR2 (1<<29)
88 #define MPC624_OSR1 (1<<28)
89 #define MPC624_OSR0 (1<<27)
91 /* 32-bit output value bits' names */
92 #define MPC624_EOC_BIT (1<<31)
93 #define MPC624_DMY_BIT (1<<30)
94 #define MPC624_SGN_BIT (1<<29)
96 /* Convertion speeds */
97 /* OSR4 OSR3 OSR2 OSR1 OSR0 Convertion rate RMS noise ENOB^
98 * X 0 0 0 1 3.52kHz 23uV 17
99 * X 0 0 1 0 1.76kHz 3.5uV 20
100 * X 0 0 1 1 880Hz 2uV 21.3
101 * X 0 1 0 0 440Hz 1.4uV 21.8
102 * X 0 1 0 1 220Hz 1uV 22.4
103 * X 0 1 1 0 110Hz 750uV 22.9
104 * X 0 1 1 1 55Hz 510nV 23.4
105 * X 1 0 0 0 27.5Hz 375nV 24
106 * X 1 0 0 1 13.75Hz 250nV 24.4
107 * X 1 1 1 1 6.875Hz 200nV 24.6
109 * ^ - Effective Number Of Bits
112 #define MPC624_SPEED_3_52_kHz (MPC624_OSR4 | MPC624_OSR0)
113 #define MPC624_SPEED_1_76_kHz (MPC624_OSR4 | MPC624_OSR1)
114 #define MPC624_SPEED_880_Hz (MPC624_OSR4 | MPC624_OSR1 | MPC624_OSR0)
115 #define MPC624_SPEED_440_Hz (MPC624_OSR4 | MPC624_OSR2)
116 #define MPC624_SPEED_220_Hz (MPC624_OSR4 | MPC624_OSR2 | MPC624_OSR0)
117 #define MPC624_SPEED_110_Hz (MPC624_OSR4 | MPC624_OSR2 | MPC624_OSR1)
118 #define MPC624_SPEED_55_Hz \
119 (MPC624_OSR4 | MPC624_OSR2 | MPC624_OSR1 | MPC624_OSR0)
120 #define MPC624_SPEED_27_5_Hz (MPC624_OSR4 | MPC624_OSR3)
121 #define MPC624_SPEED_13_75_Hz (MPC624_OSR4 | MPC624_OSR3 | MPC624_OSR0)
122 #define MPC624_SPEED_6_875_Hz \
123 (MPC624_OSR4 | MPC624_OSR3 | MPC624_OSR2 | MPC624_OSR1 | MPC624_OSR0)
124 /* -------------------------------------------------------------------------- */
125 struct skel_private {
127 /* set by mpc624_attach() from driver's parameters */
128 unsigned long int ulConvertionRate;
131 #define devpriv ((struct skel_private *)dev->private)
132 /* -------------------------------------------------------------------------- */
133 static const struct comedi_lrange range_mpc624_bipolar1 = {
136 /* BIP_RANGE(1.01) this is correct, */
137 /* but my MPC-624 actually seems to have a range of 2.02 */
142 static const struct comedi_lrange range_mpc624_bipolar10 = {
145 /* BIP_RANGE(10.1) this is correct, */
146 /* but my MPC-624 actually seems to have a range of 20.2 */
151 /* -------------------------------------------------------------------------- */
152 static int mpc624_attach(struct comedi_device *dev,
153 struct comedi_devconfig *it);
154 static int mpc624_detach(struct comedi_device *dev);
155 /* -------------------------------------------------------------------------- */
156 static struct comedi_driver driver_mpc624 = {
157 .driver_name = "mpc624",
158 .module = THIS_MODULE,
159 .attach = mpc624_attach,
160 .detach = mpc624_detach
163 /* -------------------------------------------------------------------------- */
164 static int mpc624_ai_rinsn(struct comedi_device *dev,
165 struct comedi_subdevice *s, struct comedi_insn *insn,
167 /* -------------------------------------------------------------------------- */
168 static int mpc624_attach(struct comedi_device *dev, struct comedi_devconfig *it)
170 struct comedi_subdevice *s;
171 unsigned long iobase;
173 iobase = it->options[0];
174 printk(KERN_INFO "comedi%d: mpc624 [0x%04lx, ", dev->minor, iobase);
175 if (request_region(iobase, MPC624_SIZE, "mpc624") == NULL) {
176 printk(KERN_ERR "I/O port(s) in use\n");
180 dev->iobase = iobase;
181 dev->board_name = "mpc624";
183 /* Private structure initialization */
184 if (alloc_private(dev, sizeof(struct skel_private)) < 0)
187 switch (it->options[1]) {
189 devpriv->ulConvertionRate = MPC624_SPEED_3_52_kHz;
190 printk(KERN_INFO "3.52 kHz, ");
193 devpriv->ulConvertionRate = MPC624_SPEED_1_76_kHz;
194 printk(KERN_INFO "1.76 kHz, ");
197 devpriv->ulConvertionRate = MPC624_SPEED_880_Hz;
198 printk(KERN_INFO "880 Hz, ");
201 devpriv->ulConvertionRate = MPC624_SPEED_440_Hz;
202 printk(KERN_INFO "440 Hz, ");
205 devpriv->ulConvertionRate = MPC624_SPEED_220_Hz;
206 printk(KERN_INFO "220 Hz, ");
209 devpriv->ulConvertionRate = MPC624_SPEED_110_Hz;
210 printk(KERN_INFO "110 Hz, ");
213 devpriv->ulConvertionRate = MPC624_SPEED_55_Hz;
214 printk(KERN_INFO "55 Hz, ");
217 devpriv->ulConvertionRate = MPC624_SPEED_27_5_Hz;
218 printk(KERN_INFO "27.5 Hz, ");
221 devpriv->ulConvertionRate = MPC624_SPEED_13_75_Hz;
222 printk(KERN_INFO "13.75 Hz, ");
225 devpriv->ulConvertionRate = MPC624_SPEED_6_875_Hz;
226 printk(KERN_INFO "6.875 Hz, ");
230 (KERN_ERR "illegal convertion rate setting!"
231 " Valid numbers are 0..9. Using 9 => 6.875 Hz, ");
232 devpriv->ulConvertionRate = MPC624_SPEED_3_52_kHz;
235 /* Subdevices structures */
236 if (alloc_subdevices(dev, 1) < 0)
239 s = dev->subdevices + 0;
240 s->type = COMEDI_SUBD_AI;
241 s->subdev_flags = SDF_READABLE | SDF_DIFF;
243 switch (it->options[1]) {
245 s->maxdata = 0x3FFFFFFF;
246 printk(KERN_INFO "30 bit, ");
249 switch (it->options[1]) {
251 s->range_table = &range_mpc624_bipolar1;
252 printk(KERN_INFO "1.01V]: ");
255 s->range_table = &range_mpc624_bipolar10;
256 printk(KERN_INFO "10.1V]: ");
259 s->insn_read = mpc624_ai_rinsn;
261 printk(KERN_INFO "attached\n");
266 static int mpc624_detach(struct comedi_device *dev)
268 printk(KERN_INFO "comedi%d: mpc624: remove\n", dev->minor);
271 release_region(dev->iobase, MPC624_SIZE);
279 static int mpc624_ai_rinsn(struct comedi_device *dev,
280 struct comedi_subdevice *s, struct comedi_insn *insn,
284 unsigned long int data_in, data_out;
285 unsigned char ucPort;
289 * We always write 0 to GNSWA bit, so the channel range is +-/10.1Vdc
291 outb(insn->chanspec, dev->iobase + MPC624_GNMUXCH);
292 /* printk("Channel %d:\n", insn->chanspec); */
294 printk(KERN_INFO "MPC624: Warning, no data to acquire\n");
298 for (n = 0; n < insn->n; n++) {
299 /* Trigger the convertion */
300 outb(MPC624_ADSCK, dev->iobase + MPC624_ADC);
302 outb(MPC624_ADCS | MPC624_ADSCK, dev->iobase + MPC624_ADC);
304 outb(0, dev->iobase + MPC624_ADC);
307 /* Wait for the convertion to end */
308 for (i = 0; i < TIMEOUT; i++) {
309 ucPort = inb(dev->iobase + MPC624_ADC);
310 if (ucPort & MPC624_ADBUSY)
316 printk(KERN_ERR "MPC624: timeout (%dms)\n", TIMEOUT);
320 /* Start reading data */
322 data_out = devpriv->ulConvertionRate;
324 for (i = 0; i < 32; i++) {
325 /* Set the clock low */
326 outb(0, dev->iobase + MPC624_ADC);
329 if (data_out & (1 << 31)) { /* the next bit is a 1 */
330 /* Set the ADSDI line (send to MPC624) */
331 outb(MPC624_ADSDI, dev->iobase + MPC624_ADC);
333 /* Set the clock high */
334 outb(MPC624_ADSCK | MPC624_ADSDI,
335 dev->iobase + MPC624_ADC);
336 } else { /* the next bit is a 0 */
338 /* Set the ADSDI line (send to MPC624) */
339 outb(0, dev->iobase + MPC624_ADC);
341 /* Set the clock high */
342 outb(MPC624_ADSCK, dev->iobase + MPC624_ADC);
344 /* Read ADSDO on high clock (receive from MPC624) */
348 (inb(dev->iobase + MPC624_ADC) & MPC624_ADSDO) >> 4;
355 * Received 32-bit long value consist of:
357 * (End Of Transmission) bit - should be 0
359 * (Dummy) bit - should be 0
361 * (Sign) bit- 1 if the voltage is positive,
364 * (Most Significant Bit) - the first bit of
365 * the conversion result
368 * (Least Significant Bit)- the last bit of the
371 * - sub-LSBs are basically noise, but when
372 * averaged properly, they can increase conversion
373 * precision up to 29 bits; they can be discarded
374 * without loss of resolution.
377 if (data_in & MPC624_EOC_BIT)
378 printk(KERN_INFO "MPC624:EOC bit is set (data_in=%lu)!",
380 if (data_in & MPC624_DMY_BIT)
381 printk(KERN_INFO "MPC624:DMY bit is set (data_in=%lu)!",
383 if (data_in & MPC624_SGN_BIT) { /* Volatge is positive */
385 * comedi operates on unsigned numbers, so mask off EOC
386 * and DMY and don't clear the SGN bit
388 data_in &= 0x3FFFFFFF;
390 } else { /* The voltage is negative */
392 * data_in contains a number in 30-bit two's complement
393 * code and we must deal with it
395 data_in |= MPC624_SGN_BIT;
398 data_in &= ~(MPC624_EOC_BIT | MPC624_DMY_BIT);
399 /* clear EOC and DMY bits */
400 data_in = 0x20000000 - data_in;
405 /* Return the number of samples read/written */
409 static int __init driver_mpc624_init_module(void)
411 return comedi_driver_register(&driver_mpc624);
414 static void __exit driver_mpc624_cleanup_module(void)
416 comedi_driver_unregister(&driver_mpc624);
419 module_init(driver_mpc624_init_module);
420 module_exit(driver_mpc624_cleanup_module);
422 MODULE_AUTHOR("Comedi http://www.comedi.org");
423 MODULE_DESCRIPTION("Comedi low-level driver");
424 MODULE_LICENSE("GPL");