/* comedi/drivers/mpc624.c Hardware driver for a Micro/sys inc. MPC-624 PC/104 board COMEDI - Linux Control and Measurement Device Interface Copyright (C) 2000 David A. Schleef This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ /* Driver: mpc624 Description: Micro/sys MPC-624 PC/104 board Devices: [Micro/sys] MPC-624 (mpc624) Author: Stanislaw Raczynski Updated: Thu, 15 Sep 2005 12:01:18 +0200 Status: working The Micro/sys MPC-624 board is based on the LTC2440 24-bit sigma-delta ADC chip. Subdevices supported by the driver: - Analog In: supported - Digital I/O: not supported - LEDs: not supported - EEPROM: not supported Configuration Options: [0] - I/O base address [1] - conversion rate Conversion rate RMS noise Effective Number Of Bits 0 3.52kHz 23uV 17 1 1.76kHz 3.5uV 20 2 880Hz 2uV 21.3 3 440Hz 1.4uV 21.8 4 220Hz 1uV 22.4 5 110Hz 750uV 22.9 6 55Hz 510nV 23.4 7 27.5Hz 375nV 24 8 13.75Hz 250nV 24.4 9 6.875Hz 200nV 24.6 [2] - voltage range 0 -1.01V .. +1.01V 1 -10.1V .. +10.1V */ #include "../comedidev.h" #include #include /* Consecutive I/O port addresses */ #define MPC624_SIZE 16 /* Offsets of different ports */ #define MPC624_MASTER_CONTROL 0 /* not used */ #define MPC624_GNMUXCH 1 /* Gain, Mux, Channel of ADC */ #define MPC624_ADC 2 /* read/write to/from ADC */ #define MPC624_EE 3 /* read/write to/from serial EEPROM via I2C */ #define MPC624_LEDS 4 /* write to LEDs */ #define MPC624_DIO 5 /* read/write to/from digital I/O ports */ #define MPC624_IRQ_MASK 6 /* IRQ masking enable/disable */ /* Register bits' names */ #define MPC624_ADBUSY (1<<5) #define MPC624_ADSDO (1<<4) #define MPC624_ADFO (1<<3) #define MPC624_ADCS (1<<2) #define MPC624_ADSCK (1<<1) #define MPC624_ADSDI (1<<0) /* SDI Speed/Resolution Programming bits */ #define MPC624_OSR4 (1<<31) #define MPC624_OSR3 (1<<30) #define MPC624_OSR2 (1<<29) #define MPC624_OSR1 (1<<28) #define MPC624_OSR0 (1<<27) /* 32-bit output value bits' names */ #define MPC624_EOC_BIT (1<<31) #define MPC624_DMY_BIT (1<<30) #define MPC624_SGN_BIT (1<<29) /* Conversion speeds */ /* OSR4 OSR3 OSR2 OSR1 OSR0 Conversion rate RMS noise ENOB^ * X 0 0 0 1 3.52kHz 23uV 17 * X 0 0 1 0 1.76kHz 3.5uV 20 * X 0 0 1 1 880Hz 2uV 21.3 * X 0 1 0 0 440Hz 1.4uV 21.8 * X 0 1 0 1 220Hz 1uV 22.4 * X 0 1 1 0 110Hz 750uV 22.9 * X 0 1 1 1 55Hz 510nV 23.4 * X 1 0 0 0 27.5Hz 375nV 24 * X 1 0 0 1 13.75Hz 250nV 24.4 * X 1 1 1 1 6.875Hz 200nV 24.6 * * ^ - Effective Number Of Bits */ #define MPC624_SPEED_3_52_kHz (MPC624_OSR4 | MPC624_OSR0) #define MPC624_SPEED_1_76_kHz (MPC624_OSR4 | MPC624_OSR1) #define MPC624_SPEED_880_Hz (MPC624_OSR4 | MPC624_OSR1 | MPC624_OSR0) #define MPC624_SPEED_440_Hz (MPC624_OSR4 | MPC624_OSR2) #define MPC624_SPEED_220_Hz (MPC624_OSR4 | MPC624_OSR2 | MPC624_OSR0) #define MPC624_SPEED_110_Hz (MPC624_OSR4 | MPC624_OSR2 | MPC624_OSR1) #define MPC624_SPEED_55_Hz \ (MPC624_OSR4 | MPC624_OSR2 | MPC624_OSR1 | MPC624_OSR0) #define MPC624_SPEED_27_5_Hz (MPC624_OSR4 | MPC624_OSR3) #define MPC624_SPEED_13_75_Hz (MPC624_OSR4 | MPC624_OSR3 | MPC624_OSR0) #define MPC624_SPEED_6_875_Hz \ (MPC624_OSR4 | MPC624_OSR3 | MPC624_OSR2 | MPC624_OSR1 | MPC624_OSR0) /* -------------------------------------------------------------------------- */ struct mpc624_private { /* set by mpc624_attach() from driver's parameters */ unsigned long int ulConvertionRate; }; /* -------------------------------------------------------------------------- */ static const struct comedi_lrange range_mpc624_bipolar1 = { 1, { /* BIP_RANGE(1.01) this is correct, */ /* but my MPC-624 actually seems to have a range of 2.02 */ BIP_RANGE(2.02) } }; static const struct comedi_lrange range_mpc624_bipolar10 = { 1, { /* BIP_RANGE(10.1) this is correct, */ /* but my MPC-624 actually seems to have a range of 20.2 */ BIP_RANGE(20.2) } }; /* Timeout 200ms */ #define TIMEOUT 200 static int mpc624_ai_rinsn(struct comedi_device *dev, struct comedi_subdevice *s, struct comedi_insn *insn, unsigned int *data) { struct mpc624_private *devpriv = dev->private; int n, i; unsigned long int data_in, data_out; unsigned char ucPort; /* * WARNING: * We always write 0 to GNSWA bit, so the channel range is +-/10.1Vdc */ outb(insn->chanspec, dev->iobase + MPC624_GNMUXCH); /* printk("Channel %d:\n", insn->chanspec); */ if (!insn->n) { printk(KERN_INFO "MPC624: Warning, no data to acquire\n"); return 0; } for (n = 0; n < insn->n; n++) { /* Trigger the conversion */ outb(MPC624_ADSCK, dev->iobase + MPC624_ADC); udelay(1); outb(MPC624_ADCS | MPC624_ADSCK, dev->iobase + MPC624_ADC); udelay(1); outb(0, dev->iobase + MPC624_ADC); udelay(1); /* Wait for the conversion to end */ for (i = 0; i < TIMEOUT; i++) { ucPort = inb(dev->iobase + MPC624_ADC); if (ucPort & MPC624_ADBUSY) udelay(1000); else break; } if (i == TIMEOUT) { printk(KERN_ERR "MPC624: timeout (%dms)\n", TIMEOUT); data[n] = 0; return -ETIMEDOUT; } /* Start reading data */ data_in = 0; data_out = devpriv->ulConvertionRate; udelay(1); for (i = 0; i < 32; i++) { /* Set the clock low */ outb(0, dev->iobase + MPC624_ADC); udelay(1); if (data_out & (1 << 31)) { /* the next bit is a 1 */ /* Set the ADSDI line (send to MPC624) */ outb(MPC624_ADSDI, dev->iobase + MPC624_ADC); udelay(1); /* Set the clock high */ outb(MPC624_ADSCK | MPC624_ADSDI, dev->iobase + MPC624_ADC); } else { /* the next bit is a 0 */ /* Set the ADSDI line (send to MPC624) */ outb(0, dev->iobase + MPC624_ADC); udelay(1); /* Set the clock high */ outb(MPC624_ADSCK, dev->iobase + MPC624_ADC); } /* Read ADSDO on high clock (receive from MPC624) */ udelay(1); data_in <<= 1; data_in |= (inb(dev->iobase + MPC624_ADC) & MPC624_ADSDO) >> 4; udelay(1); data_out <<= 1; } /* * Received 32-bit long value consist of: * 31: EOC - * (End Of Transmission) bit - should be 0 * 30: DMY * (Dummy) bit - should be 0 * 29: SIG * (Sign) bit- 1 if the voltage is positive, * 0 if negative * 28: MSB * (Most Significant Bit) - the first bit of * the conversion result * .... * 05: LSB * (Least Significant Bit)- the last bit of the * conversion result * 04-00: sub-LSB * - sub-LSBs are basically noise, but when * averaged properly, they can increase conversion * precision up to 29 bits; they can be discarded * without loss of resolution. */ if (data_in & MPC624_EOC_BIT) printk(KERN_INFO "MPC624:EOC bit is set (data_in=%lu)!", data_in); if (data_in & MPC624_DMY_BIT) printk(KERN_INFO "MPC624:DMY bit is set (data_in=%lu)!", data_in); if (data_in & MPC624_SGN_BIT) { /* Volatge is positive */ /* * comedi operates on unsigned numbers, so mask off EOC * and DMY and don't clear the SGN bit */ data_in &= 0x3FFFFFFF; data[n] = data_in; } else { /* The voltage is negative */ /* * data_in contains a number in 30-bit two's complement * code and we must deal with it */ data_in |= MPC624_SGN_BIT; data_in = ~data_in; data_in += 1; data_in &= ~(MPC624_EOC_BIT | MPC624_DMY_BIT); /* clear EOC and DMY bits */ data_in = 0x20000000 - data_in; data[n] = data_in; } } /* Return the number of samples read/written */ return n; } static int mpc624_attach(struct comedi_device *dev, struct comedi_devconfig *it) { struct mpc624_private *devpriv; struct comedi_subdevice *s; int ret; ret = comedi_request_region(dev, it->options[0], MPC624_SIZE); if (ret) return ret; devpriv = kzalloc(sizeof(*devpriv), GFP_KERNEL); if (!devpriv) return -ENOMEM; dev->private = devpriv; switch (it->options[1]) { case 0: devpriv->ulConvertionRate = MPC624_SPEED_3_52_kHz; break; case 1: devpriv->ulConvertionRate = MPC624_SPEED_1_76_kHz; break; case 2: devpriv->ulConvertionRate = MPC624_SPEED_880_Hz; break; case 3: devpriv->ulConvertionRate = MPC624_SPEED_440_Hz; break; case 4: devpriv->ulConvertionRate = MPC624_SPEED_220_Hz; break; case 5: devpriv->ulConvertionRate = MPC624_SPEED_110_Hz; break; case 6: devpriv->ulConvertionRate = MPC624_SPEED_55_Hz; break; case 7: devpriv->ulConvertionRate = MPC624_SPEED_27_5_Hz; break; case 8: devpriv->ulConvertionRate = MPC624_SPEED_13_75_Hz; break; case 9: devpriv->ulConvertionRate = MPC624_SPEED_6_875_Hz; break; default: devpriv->ulConvertionRate = MPC624_SPEED_3_52_kHz; } ret = comedi_alloc_subdevices(dev, 1); if (ret) return ret; s = &dev->subdevices[0]; s->type = COMEDI_SUBD_AI; s->subdev_flags = SDF_READABLE | SDF_DIFF; s->n_chan = 8; switch (it->options[1]) { default: s->maxdata = 0x3FFFFFFF; } switch (it->options[1]) { case 0: s->range_table = &range_mpc624_bipolar1; break; default: s->range_table = &range_mpc624_bipolar10; } s->len_chanlist = 1; s->insn_read = mpc624_ai_rinsn; return 1; } static struct comedi_driver mpc624_driver = { .driver_name = "mpc624", .module = THIS_MODULE, .attach = mpc624_attach, .detach = comedi_legacy_detach, }; module_comedi_driver(mpc624_driver); MODULE_AUTHOR("Comedi http://www.comedi.org"); MODULE_DESCRIPTION("Comedi low-level driver"); MODULE_LICENSE("GPL");