In int mode, data from DAQ are counts but LSL expects signed ints, so we subtract the midpoint.

Author: cboulay

src/core/src/Device.cpp

@@ -537,9 +537,11 @@ bool MCCDevice::getDataInt32(std::vector<int32_t>& buffer, double& timestamp) {
             size_t read_offset =
                 (static_cast<size_t>(scans_read_) * channelCount) % total_buffer_elements;
 
+            const int64_t mid = 1LL << (capabilities_.resolution_bits - 1);
             for (size_t i = 0; i < num_elements; ++i) {
-                buffer[i] = static_cast<int32_t>(
+                auto raw = static_cast<int64_t>(
                     scan_buffer_[(read_offset + i) % total_buffer_elements]);
+                buffer[i] = static_cast<int32_t>(raw - mid);
             }
 
             scans_read_ += available;
@@ -581,9 +583,11 @@ bool MCCDevice::getDataInt16(std::vector<int16_t>& buffer, double& timestamp) {
             size_t read_offset =
                 (static_cast<size_t>(scans_read_) * channelCount) % total_buffer_elements;
 
+            const int32_t mid = 1 << (capabilities_.resolution_bits - 1);
             for (size_t i = 0; i < num_elements; ++i) {
-                buffer[i] = static_cast<int16_t>(
+                auto raw = static_cast<int32_t>(
                     scan_buffer_[(read_offset + i) % total_buffer_elements]);
+                buffer[i] = static_cast<int16_t>(raw - mid);
             }
 
             scans_read_ += available;

src/core/src/LSLOutlet.cpp

@@ -40,7 +40,7 @@ LSLOutlet::LSLOutlet(const DeviceInfo& info)
         double full_scale = std::pow(2.0, info.resolution_bits);
         double span = info.range_max - info.range_min;
         double slope = span / full_scale;
-        double offset = info.range_min;
+        double offset = (info.range_min + info.range_max) / 2.0;
         acq.append_child_value("scaling_slope", std::to_string(slope));
         acq.append_child_value("scaling_offset", std::to_string(offset));
     }