From 9c3f912d1a78c3275d5a6ed055b16029c818c1f5 Mon Sep 17 00:00:00 2001
From: William Clark <wrvc96@gmail.com>
Date: Fri, 29 Dec 2023 18:19:11 +0000
Subject: [PATCH] read REFERENCE

---
 lis3dh.c | 7 +++++++
 lis3dh.h | 5 +++--
 2 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/lis3dh.c b/lis3dh.c
index f1a69d7..5b21aba 100644
--- a/lis3dh.c
+++ b/lis3dh.c
@@ -348,4 +348,11 @@ int lis3dh_clear_int1(lis3dh_t *lis3dh) {
 int lis3dh_clear_int2(lis3dh_t *lis3dh) {
     uint8_t res;
     return lis3dh->dev.read(REG_INT2_SRC, &res, 1);
+}
+
+/* read REFERENCE reg to reset HP filter in REFERENCE mode
+   it uses the --current-- acceleration as the base in the filter */
+int lis3dh_reference(lis3dh_t *lis3dh) {
+    uint8_t res;
+    return lis3dh->dev.read(REG_REFERENCE, &res, 1);
 }
\ No newline at end of file
diff --git a/lis3dh.h b/lis3dh.h
index 5ce88c7..e48de43 100644
--- a/lis3dh.h
+++ b/lis3dh.h
@@ -70,7 +70,7 @@ struct lis3dh_int2_config {
     uint8_t boot; /* enable BOOT on pin 2 */
     uint8_t act; /* interrupt on activity */
     uint8_t polarity; /* INT1 & INT2 polarity. 0 active high, 1 active low */
-    uint8_t latch;
+    uint8_t latch;  /* latch interrupt until cleared */
 };
 
 struct lis3dh_int1_config {
@@ -81,7 +81,7 @@ struct lis3dh_int1_config {
     uint8_t drdy_321; /* not sure */
     uint8_t wtm; /* FIFO reached watermark level */
     uint8_t overrun; /* FIFO has overrun */
-    uint8_t latch;
+    uint8_t latch; /* latch interrupt until cleared */
 };
 
 struct lis3dh_filter_config {
@@ -140,6 +140,7 @@ int lis3dh_poll_fifo(lis3dh_t *lis3dh);
 int lis3dh_read_fifo(lis3dh_t *lis3dh, struct lis3dh_fifo_data *fifo);
 int lis3dh_clear_int1(lis3dh_t *lis3dh);
 int lis3dh_clear_int2(lis3dh_t *lis3dh);
+int lis3dh_reference(lis3dh_t *lis3dh);