// // Created by MightyPork on 2018/01/29. // #include "comm/messages.h" #include "unit_base.h" #include "unit_1wire.h" // 1WIRE master #define OW_INTERNAL #include "_ow_internal.h" #include "_ow_low_level.h" /** * 1-Wire timer callback, used for the 'wait_ready' function. * * - In parasitic mode, this is a simple 750ms wait, after which a SUCCESS response is sent. * - In 3-wire mode, the callback is fired periodically and performs a Read operation on the bus. * The unit responds with 0 while the operation is ongoing. On receiving 1 a SUCCESS response is sent. * The polling is abandoned after a timeout, sending a TIMEOUT response. * * @param xTimer */ void OW_TimerCb(TimerHandle_t xTimer) { Unit *unit = pvTimerGetTimerID(xTimer); assert_param(unit); struct priv *priv = unit->data; assert_param(priv->busy); // XXX Possible bug // This is run on the timers thread. The TF write functions block on a semaphore. // The FreeRTOS documentation warns against blocking in the timers thread, // but does not say why. This can be solved by scheduling the response using the job queue. if (priv->parasitic) { // this is the end of the 750ms measurement time goto halt_ok; } else { bool ready = ow_read_bit(unit); if (ready) { goto halt_ok; } uint32_t time = PTIM_GetTime(); if (time - priv->busyStart > 1000) { xTimerStop(xTimer, 100); com_respond_error(priv->busyRequestId, E_HW_TIMEOUT); priv->busy = false; } } return; halt_ok: xTimerStop(xTimer, 100); com_respond_ok(priv->busyRequestId); priv->busy = false; } enum PinCmd_ { CMD_CHECK_PRESENCE = 0, // simply tests that any devices are attached CMD_SEARCH_ADDR = 1, // perform a scan of the bus, retrieving all found device ROMs CMD_SEARCH_ALARM = 2, // like normal scan, but retrieve only devices with alarm CMD_SEARCH_CONTINUE = 3, // continue the previously started scan, retrieving more devices CMD_READ_ADDR = 4, // read the ROM code from a single device (for single-device bus) CMD_WRITE = 10, // write multiple bytes using the SKIP_ROM command CMD_READ = 11, // write multiple bytes using a ROM address CMD_POLL_FOR_1 = 20, CMD_TEST = 100, }; /** Handle a request message */ static error_t OW_handleRequest(Unit *unit, TF_ID frame_id, uint8_t command, PayloadParser *pp) { struct priv *priv = unit->data; bool presence; uint64_t addr; uint32_t remain; const uint8_t *tail; if (priv->busy) return E_BUSY; bool with_alarm = false; bool search_reset = false; switch (command) { /** * This is the delay function for DS1820 measurements. * * Parasitic: Returns success after the required 750ms * Non-parasitic: Returns SUCCESS after device responds '1', HW_TIMEOUT after 1s */ case CMD_POLL_FOR_1: // This can't be exposed via the UU API, due to being async if (priv->parasitic) { assert_param(pdPASS == xTimerChangePeriod(priv->busyWaitTimer, 750, 100)); } else { // every 10 ticks assert_param(pdPASS == xTimerChangePeriod(priv->busyWaitTimer, 10, 100)); } assert_param(pdPASS == xTimerStart(priv->busyWaitTimer, 100)); priv->busy = true; priv->busyStart = PTIM_GetTime(); priv->busyRequestId = frame_id; return E_SUCCESS; // We will respond when the timer expires case CMD_SEARCH_ALARM: with_alarm = true; // fall-through case CMD_SEARCH_ADDR: search_reset = true; // fall-through case CMD_SEARCH_CONTINUE:; uint32_t found_count = 0; bool have_more = false; TRY(UU_1WIRE_Search(unit, with_alarm, search_reset, (void *) unit_tmp512, UNIT_TMP_LEN/8, &found_count, &have_more)); // use multipart to avoid allocating extra buffer uint8_t status_code = (uint8_t) have_more; TF_Msg msg = { .frame_id = frame_id, .type = MSG_SUCCESS, .len = (TF_LEN) (found_count * 8 + 1), }; TF_Respond_Multipart(comm, &msg); TF_Multipart_Payload(comm, &status_code, 1); // the codes are back-to-back stored inside the buffer, we send it directly // (it's already little-endian, as if built by PayloadBuilder) TF_Multipart_Payload(comm, (uint8_t *) unit_tmp512, found_count * 8); TF_Multipart_Close(comm); return E_SUCCESS; /** Simply check presence of any devices on the bus. Responds with SUCCESS or HW_TIMEOUT */ case CMD_CHECK_PRESENCE: TRY(UU_1WIRE_CheckPresence(unit, &presence)); com_respond_u8(frame_id, (uint8_t) presence); return E_SUCCESS; /** Read address of the single device on the bus - returns u64 */ case CMD_READ_ADDR: TRY(UU_1WIRE_ReadAddress(unit, &addr)); // build response PayloadBuilder pb = pb_start(unit_tmp512, UNIT_TMP_LEN, NULL); pb_u64(&pb, addr); com_respond_pb(frame_id, MSG_SUCCESS, &pb); return E_SUCCESS; /** * Write payload to the bus, no confirmation (unless requested). * * Payload: * - Match variant: addr:u64, rest:write_data * - Skip variant: all:write_data */ case CMD_WRITE: addr = pp_u64(pp); tail = pp_tail(pp, &remain); TRY(UU_1WIRE_Write(unit, addr, tail, remain)); return E_SUCCESS; /** * Write and read. * * Payload: * - Match variant: addr:u64, read_len:u16, rest:write_data * - Skip variant: read_len:u16, rest:write_data */ case CMD_READ:; addr = pp_u64(pp); uint16_t rcount = pp_u16(pp); bool test_crc = pp_bool(pp); tail = pp_tail(pp, &remain); TRY(UU_1WIRE_Read(unit, addr, tail, remain, (uint8_t *) unit_tmp512, rcount, test_crc)); // build response com_respond_buf(frame_id, MSG_SUCCESS, (uint8_t *) unit_tmp512, rcount); return E_SUCCESS; default: return E_UNKNOWN_COMMAND; } } // ------------------------------------------------------------------------ /** Unit template */ const UnitDriver UNIT_1WIRE = { .name = "1WIRE", .description = "1-Wire master", // Settings .preInit = OW_preInit, .cfgLoadBinary = OW_loadBinary, .cfgWriteBinary = OW_writeBinary, .cfgLoadIni = OW_loadIni, .cfgWriteIni = OW_writeIni, // Init .init = OW_init, .deInit = OW_deInit, // Function .handleRequest = OW_handleRequest, };