From: Ian Abbott <abbotti@mev.co.uk>
Date: Wed, 12 Aug 2009 16:04:43 +0000 (+0000)
Subject: When reading DO subdevice with inverted outputs invert the values read back
X-Git-Url: http://git.tremily.us/gitweb.cgi?a=commitdiff_plain;h=63a144d56188e96c2c8eddb63208e8798542e0d3;p=comedi.git

When reading DO subdevice with inverted outputs invert the values read back
from the ports to match the inversion of values written.
---

diff --git a/comedi/drivers/ni_65xx.c b/comedi/drivers/ni_65xx.c
index ebb45cfa..8abbff99 100644
--- a/comedi/drivers/ni_65xx.c
+++ b/comedi/drivers/ni_65xx.c
@@ -440,6 +440,12 @@ static int ni_65xx_dio_insn_bits(comedi_device * dev, comedi_subdevice * s,
 			readb(private(dev)->mite->daq_io_addr +
 			Port_Data(port));
 //              rt_printk("read 0x%x from port %i\n", port_read_bits, port);
+		if (s->type == COMEDI_SUBD_DO && board(dev)->invert_outputs) {
+			/* Outputs inverted, so invert value read back from
+			 * DO subdevice.  (Does not apply to boards with DIO
+			 * subdevice.) */
+			port_read_bits ^= 0xFF;
+		}
 		if (bitshift > 0) {
 			port_read_bits <<= bitshift;
 		} else {