@@ -175,6 +175,23 @@ MP_DEFINE_CONST_FUN_OBJ_1(bitbangio_i2c_unlock_obj, bitbangio_i2c_obj_unlock);
175175//| :param int start: Index to start writing at
176176//| :param int end: Index to write up to but not include
177177//|
178+ // Shared arg parsing for readfrom_into and writeto_then_readfrom.
179+ STATIC void readfrom (bitbangio_i2c_obj_t * self , mp_int_t address , mp_obj_t buffer , int32_t start , mp_int_t end ) {
180+ mp_buffer_info_t bufinfo ;
181+ mp_get_buffer_raise (buffer , & bufinfo , MP_BUFFER_WRITE );
182+
183+ size_t length = bufinfo .len ;
184+ normalize_buffer_bounds (& start , end , & length );
185+ if (length == 0 ) {
186+ mp_raise_ValueError (translate ("Buffer must be at least length 1" ));
187+ }
188+
189+ uint8_t status = shared_module_bitbangio_i2c_read (self , address , ((uint8_t * )bufinfo .buf ) + start , length );
190+ if (status != 0 ) {
191+ mp_raise_OSError (status );
192+ }
193+ }
194+
178195STATIC mp_obj_t bitbangio_i2c_readfrom_into (size_t n_args , const mp_obj_t * pos_args , mp_map_t * kw_args ) {
179196 enum { ARG_address , ARG_buffer , ARG_start , ARG_end };
180197 static const mp_arg_t allowed_args [] = {
@@ -185,33 +202,21 @@ STATIC mp_obj_t bitbangio_i2c_readfrom_into(size_t n_args, const mp_obj_t *pos_a
185202 };
186203 bitbangio_i2c_obj_t * self = MP_OBJ_TO_PTR (pos_args [0 ]);
187204 check_for_deinit (self );
205+ check_lock (self );
188206 mp_arg_val_t args [MP_ARRAY_SIZE (allowed_args )];
189207 mp_arg_parse_all (n_args - 1 , pos_args + 1 , kw_args , MP_ARRAY_SIZE (allowed_args ), allowed_args , args );
190- check_lock (self );
191- mp_buffer_info_t bufinfo ;
192- mp_get_buffer_raise (args [ARG_buffer ].u_obj , & bufinfo , MP_BUFFER_WRITE );
193208
194- int32_t start = args [ARG_start ].u_int ;
195- uint32_t length = bufinfo .len ;
196- normalize_buffer_bounds (& start , args [ARG_end ].u_int , & length );
197- if (length == 0 ) {
198- mp_raise_ValueError (translate ("Buffer must be at least length 1" ));
199- }
200- uint8_t status = shared_module_bitbangio_i2c_read (self ,
201- args [ARG_address ].u_int ,
202- ((uint8_t * )bufinfo .buf ) + start ,
203- length );
204- if (status != 0 ) {
205- mp_raise_OSError (status );
206- }
209+ readfrom (self , args [ARG_address ].u_int , args [ARG_buffer ].u_obj , args [ARG_start ].u_int ,
210+ args [ARG_end ].u_int );
207211 return mp_const_none ;
208212}
209213MP_DEFINE_CONST_FUN_OBJ_KW (bitbangio_i2c_readfrom_into_obj , 3 , bitbangio_i2c_readfrom_into );
210214
211215//| .. method:: writeto(address, buffer, *, start=0, end=None, stop=True)
212216//|
213- //| Write the bytes from ``buffer`` to the slave specified by ``address``.
214- //| Transmits a stop bit if ``stop`` is set.
217+ //| Write the bytes from ``buffer`` to the slave specified by ``address`` and then transmits a
218+ //| stop bit. Use `writeto_then_readfrom` when needing a write, no stop and repeated start
219+ //| before a read.
215220//|
216221//| If ``start`` or ``end`` is provided, then the buffer will be sliced
217222//| as if ``buffer[start:end]``. This will not cause an allocation like
@@ -224,9 +229,27 @@ MP_DEFINE_CONST_FUN_OBJ_KW(bitbangio_i2c_readfrom_into_obj, 3, bitbangio_i2c_rea
224229//| :param bytearray buffer: buffer containing the bytes to write
225230//| :param int start: Index to start writing from
226231//| :param int end: Index to read up to but not include
227- //| :param bool stop: If true, output an I2C stop condition after the
228- //| buffer is written
232+ //| :param bool stop: If true, output an I2C stop condition after the buffer is written.
233+ //| Deprecated. Will be removed in 6.x and act as stop=True.
229234//|
235+ // Shared arg parsing for writeto and writeto_then_readfrom.
236+ STATIC void writeto (bitbangio_i2c_obj_t * self , mp_int_t address , mp_obj_t buffer , int32_t start , mp_int_t end , bool stop ) {
237+ // get the buffer to write the data from
238+ mp_buffer_info_t bufinfo ;
239+ mp_get_buffer_raise (buffer , & bufinfo , MP_BUFFER_READ );
240+
241+ size_t length = bufinfo .len ;
242+ normalize_buffer_bounds (& start , end , & length );
243+
244+ // do the transfer
245+ uint8_t status = shared_module_bitbangio_i2c_write (self , address ,
246+ ((uint8_t * ) bufinfo .buf ) + start , length ,
247+ stop );
248+ if (status != 0 ) {
249+ mp_raise_OSError (status );
250+ }
251+ }
252+
230253STATIC mp_obj_t bitbangio_i2c_writeto (size_t n_args , const mp_obj_t * pos_args , mp_map_t * kw_args ) {
231254 enum { ARG_address , ARG_buffer , ARG_start , ARG_end , ARG_stop };
232255 static const mp_arg_t allowed_args [] = {
@@ -242,23 +265,56 @@ STATIC mp_obj_t bitbangio_i2c_writeto(size_t n_args, const mp_obj_t *pos_args, m
242265 mp_arg_val_t args [MP_ARRAY_SIZE (allowed_args )];
243266 mp_arg_parse_all (n_args - 1 , pos_args + 1 , kw_args , MP_ARRAY_SIZE (allowed_args ), allowed_args , args );
244267
245- // get the buffer to write the data from
246- mp_buffer_info_t bufinfo ;
247- mp_get_buffer_raise (args [ARG_buffer ].u_obj , & bufinfo , MP_BUFFER_READ );
268+ writeto (self , args [ARG_address ].u_int , args [ARG_buffer ].u_obj , args [ARG_start ].u_int ,
269+ args [ARG_end ].u_int , args [ARG_stop ].u_bool );
270+ return mp_const_none ;
271+ }
272+ STATIC MP_DEFINE_CONST_FUN_OBJ_KW (bitbangio_i2c_writeto_obj , 1 , bitbangio_i2c_writeto );
248273
249- int32_t start = args [ARG_start ].u_int ;
250- uint32_t length = bufinfo .len ;
251- normalize_buffer_bounds (& start , args [ARG_end ].u_int , & length );
252274
253- // do the transfer
254- uint8_t status = shared_module_bitbangio_i2c_write (self , args [ARG_address ].u_int ,
255- ((uint8_t * ) bufinfo .buf ) + start , length , args [ARG_stop ].u_bool );
256- if (status != 0 ) {
257- mp_raise_OSError (status );
258- }
275+ //| .. method:: writeto_then_readfrom(address, out_buffer, in_buffer, *, out_start=0, out_end=None, in_start=0, in_end=None)
276+ //|
277+ //| Write the bytes from ``out_buffer`` to the slave specified by ``address``, generate no stop
278+ //| bit, generate a repeated start and read into ``in_buffer``. ``out_buffer`` and
279+ //| ``in_buffer`` can be the same buffer because they are used sequentially.
280+ //|
281+ //| If ``start`` or ``end`` is provided, then the corresponding buffer will be sliced
282+ //| as if ``buffer[start:end]``. This will not cause an allocation like ``buf[start:end]``
283+ //| will so it saves memory.
284+ //|
285+ //| :param int address: 7-bit device address
286+ //| :param bytearray out_buffer: buffer containing the bytes to write
287+ //| :param bytearray in_buffer: buffer to write into
288+ //| :param int out_start: Index to start writing from
289+ //| :param int out_end: Index to read up to but not include. Defaults to ``len(buffer)``
290+ //| :param int in_start: Index to start writing at
291+ //| :param int in_end: Index to write up to but not include. Defaults to ``len(buffer)``
292+ //|
293+ STATIC mp_obj_t bitbangio_i2c_writeto_then_readfrom (size_t n_args , const mp_obj_t * pos_args , mp_map_t * kw_args ) {
294+ enum { ARG_address , ARG_out_buffer , ARG_in_buffer , ARG_out_start , ARG_out_end , ARG_in_start , ARG_in_end };
295+ static const mp_arg_t allowed_args [] = {
296+ { MP_QSTR_address , MP_ARG_REQUIRED | MP_ARG_INT , {.u_int = 0 } },
297+ { MP_QSTR_out_buffer , MP_ARG_REQUIRED | MP_ARG_OBJ , {.u_obj = MP_OBJ_NULL } },
298+ { MP_QSTR_in_buffer , MP_ARG_REQUIRED | MP_ARG_OBJ , {.u_obj = MP_OBJ_NULL } },
299+ { MP_QSTR_out_start , MP_ARG_KW_ONLY | MP_ARG_INT , {.u_int = 0 } },
300+ { MP_QSTR_out_end , MP_ARG_KW_ONLY | MP_ARG_INT , {.u_int = INT_MAX } },
301+ { MP_QSTR_in_start , MP_ARG_KW_ONLY | MP_ARG_INT , {.u_int = 0 } },
302+ { MP_QSTR_in_end , MP_ARG_KW_ONLY | MP_ARG_INT , {.u_int = INT_MAX } },
303+ };
304+ bitbangio_i2c_obj_t * self = MP_OBJ_TO_PTR (pos_args [0 ]);
305+ check_for_deinit (self );
306+ check_lock (self );
307+ mp_arg_val_t args [MP_ARRAY_SIZE (allowed_args )];
308+ mp_arg_parse_all (n_args - 1 , pos_args + 1 , kw_args , MP_ARRAY_SIZE (allowed_args ), allowed_args , args );
309+
310+ writeto (self , args [ARG_address ].u_int , args [ARG_out_buffer ].u_obj , args [ARG_out_start ].u_int ,
311+ args [ARG_out_end ].u_int , false);
312+ readfrom (self , args [ARG_address ].u_int , args [ARG_in_buffer ].u_obj , args [ARG_in_start ].u_int ,
313+ args [ARG_in_end ].u_int );
314+
259315 return mp_const_none ;
260316}
261- STATIC MP_DEFINE_CONST_FUN_OBJ_KW (bitbangio_i2c_writeto_obj , 1 , bitbangio_i2c_writeto );
317+ MP_DEFINE_CONST_FUN_OBJ_KW (bitbangio_i2c_writeto_then_readfrom_obj , 3 , bitbangio_i2c_writeto_then_readfrom );
262318
263319STATIC const mp_rom_map_elem_t bitbangio_i2c_locals_dict_table [] = {
264320 { MP_ROM_QSTR (MP_QSTR_deinit ), MP_ROM_PTR (& bitbangio_i2c_deinit_obj ) },
@@ -271,6 +327,7 @@ STATIC const mp_rom_map_elem_t bitbangio_i2c_locals_dict_table[] = {
271327
272328 { MP_ROM_QSTR (MP_QSTR_writeto ), MP_ROM_PTR (& bitbangio_i2c_writeto_obj ) },
273329 { MP_ROM_QSTR (MP_QSTR_readfrom_into ), MP_ROM_PTR (& bitbangio_i2c_readfrom_into_obj ) },
330+ { MP_ROM_QSTR (MP_QSTR_writeto_then_readfrom ), MP_ROM_PTR (& bitbangio_i2c_writeto_then_readfrom_obj ) },
274331};
275332
276333STATIC MP_DEFINE_CONST_DICT (bitbangio_i2c_locals_dict , bitbangio_i2c_locals_dict_table );
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