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diff --git a/circuitpython/shared-bindings/bitops/__init__.c b/circuitpython/shared-bindings/bitops/__init__.c
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+++ b/circuitpython/shared-bindings/bitops/__init__.c
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+/*
+ * This file is part of the CircuitPython project, https://github.com/adafruit/circuitpython
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2021 Jeff Epler for Adafruit Industries
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "py/obj.h"
+#include "py/runtime.h"
+
+#include "shared-bindings/bitops/__init__.h"
+
+//| """Routines for low-level manipulation of binary data"""
+//|
+//|
+
+//| def bit_transpose(input: ReadableBuffer, output: WriteableBuffer, width:int = 8) -> WriteableBuffer:
+//|     """"Transpose" a buffer by assembling each output byte with bits taken from each of ``width`` different input bytes.
+//|
+//|     This can be useful to convert a sequence of pixel values into a single
+//|     stream of bytes suitable for sending via a parallel conversion method.
+//|
+//|     The number of bytes in the input buffer must be a multiple of the width,
+//|     and the width can be any value from 2 to 8.  If the width is fewer than 8,
+//|     then the remaining (less significant) bits of the output are set to zero.
+//|
+//|     Let ``stride = len(input)//width``.  Then the first byte is made out of the
+//|     most significant bits of ``[input[0], input[stride], input[2*stride], ...]``.
+//|     The second byte is made out of the second bits, and so on until the 8th output
+//|     byte which is made of the first bits of ``input[1], input[1+stride,
+//|     input[2*stride], ...]``.
+//|
+//|     The required output buffer size is ``len(input) * 8  // width``.
+//|
+//|     Returns the output buffer."""
+//|     ...
+
+STATIC mp_obj_t bit_transpose(size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
+    enum { ARG_input, ARG_output, ARG_width };
+    static const mp_arg_t allowed_args[] = {
+        { MP_QSTR_input, MP_ARG_OBJ | MP_ARG_REQUIRED },
+        { MP_QSTR_output, MP_ARG_OBJ | MP_ARG_REQUIRED },
+        { MP_QSTR_width, MP_ARG_INT, { .u_int = 8 } },
+    };
+    mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)];
+    mp_arg_parse_all(n_args, pos_args, kw_args, MP_ARRAY_SIZE(allowed_args), allowed_args, args);
+
+    int width = args[ARG_width].u_int;
+    if (width < 2 || width > 8) {
+        mp_raise_ValueError_varg(translate("width must be from 2 to 8 (inclusive), not %d"), width);
+    }
+
+    mp_buffer_info_t input_bufinfo;
+    mp_get_buffer_raise(args[ARG_input].u_obj, &input_bufinfo, MP_BUFFER_READ);
+    int inlen = input_bufinfo.len;
+    if (inlen % width != 0) {
+        mp_raise_ValueError_varg(translate("Input buffer length (%d) must be a multiple of the strand count (%d)"), inlen, width);
+    }
+
+    mp_buffer_info_t output_bufinfo;
+    mp_get_buffer_raise(args[ARG_output].u_obj, &output_bufinfo, MP_BUFFER_WRITE);
+    int avail = output_bufinfo.len;
+    int outlen = 8 * (inlen / width);
+    if (avail < outlen) {
+        mp_raise_ValueError_varg(translate("Output buffer must be at least %d bytes"), outlen);
+    }
+    common_hal_bitops_bit_transpose(output_bufinfo.buf, input_bufinfo.buf, inlen, width);
+    return args[ARG_output].u_obj;
+}
+STATIC MP_DEFINE_CONST_FUN_OBJ_KW(bitops_bit_transpose_obj, 0, bit_transpose);
+
+STATIC const mp_rom_map_elem_t bitops_module_globals_table[] = {
+    { MP_ROM_QSTR(MP_QSTR___name__), MP_ROM_QSTR(MP_QSTR_bitops) },
+    { MP_ROM_QSTR(MP_QSTR_bit_transpose), MP_ROM_PTR(&bitops_bit_transpose_obj) },
+};
+
+STATIC MP_DEFINE_CONST_DICT(bitops_module_globals, bitops_module_globals_table);
+
+const mp_obj_module_t bitops_module = {
+    .base = { &mp_type_module },
+    .globals = (mp_obj_dict_t *)&bitops_module_globals,
+};
+
+MP_REGISTER_MODULE(MP_QSTR_bitops, bitops_module, CIRCUITPY_BITOPS);