diff --git a/doc/hardware/hlk7628/manual.pdf b/doc/hardware/hlk7628/manual.pdf
new file mode 100644
index 0000000..d5826bb
Binary files /dev/null and b/doc/hardware/hlk7628/manual.pdf differ
diff --git a/doc/hardware/hlk7628/manual_pinouts.pdf b/doc/hardware/hlk7628/manual_pinouts.pdf
new file mode 100644
index 0000000..23bf2bf
Binary files /dev/null and b/doc/hardware/hlk7628/manual_pinouts.pdf differ
diff --git a/doc/hardware/xr22801/XR22801.pdf b/doc/hardware/xr22801/XR22801.pdf
new file mode 100644
index 0000000..fd454af
Binary files /dev/null and b/doc/hardware/xr22801/XR22801.pdf differ
diff --git a/doc/hardware/xr22801/XR22801_REV_20_09242015.pdf b/doc/hardware/xr22801/XR22801_REV_20_09242015.pdf
new file mode 100644
index 0000000..eef8bce
Binary files /dev/null and b/doc/hardware/xr22801/XR22801_REV_20_09242015.pdf differ