An RTOS-friendly Serial interface Its primary benefit is that it never hogs the CPU. An amusing alternative to the traditional ring-bufferd interrupt-serviced systems, it uses short mbed-rtos queues to buffer characters to and from the UART, and a thread to service the transmitter. Short interrupt service routines enqueue received characters and signal the transmit thread when the transmitter is available. WARNING: Do not create RTOS-Serial objects before the RTOS is running! Put them inside your main() block or another function, not in the global initialization.
Dependents: Test_RDM880_rfid_reader
rtos_serial.cpp@1:5a66fddad7c4, 2013-10-18 (annotated)
- Committer:
- altasoul
- Date:
- Fri Oct 18 03:39:24 2013 +0000
- Revision:
- 1:5a66fddad7c4
- Parent:
- 0:0547c8bf304f
- Child:
- 2:891773cc33fd
checkpoint
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
altasoul | 0:0547c8bf304f | 1 | /* |
altasoul | 0:0547c8bf304f | 2 | * Copyright (c) 2013 Tom Soulanille |
altasoul | 0:0547c8bf304f | 3 | * |
altasoul | 0:0547c8bf304f | 4 | * Permission is hereby granted, free of charge, to any person obtaining a copy |
altasoul | 0:0547c8bf304f | 5 | * of this software and associated documentation files (the "Software"), to deal |
altasoul | 0:0547c8bf304f | 6 | * in the Software without restriction, including without limitation the rights |
altasoul | 0:0547c8bf304f | 7 | * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell |
altasoul | 0:0547c8bf304f | 8 | * copies of the Software, and to permit persons to whom the Software is |
altasoul | 0:0547c8bf304f | 9 | * furnished to do so, subject to the following conditions: |
altasoul | 0:0547c8bf304f | 10 | * |
altasoul | 0:0547c8bf304f | 11 | * The above copyright notice and this permission notice shall be included in |
altasoul | 0:0547c8bf304f | 12 | * all copies or substantial portions of the Software. |
altasoul | 0:0547c8bf304f | 13 | * |
altasoul | 0:0547c8bf304f | 14 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
altasoul | 0:0547c8bf304f | 15 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
altasoul | 0:0547c8bf304f | 16 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE |
altasoul | 0:0547c8bf304f | 17 | * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
altasoul | 0:0547c8bf304f | 18 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, |
altasoul | 0:0547c8bf304f | 19 | * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE |
altasoul | 0:0547c8bf304f | 20 | * SOFTWARE. |
altasoul | 0:0547c8bf304f | 21 | */ |
altasoul | 0:0547c8bf304f | 22 | |
altasoul | 0:0547c8bf304f | 23 | #include "rtos_serial.h" |
altasoul | 0:0547c8bf304f | 24 | |
altasoul | 0:0547c8bf304f | 25 | //RTOS_Serial::tx_mail_t blah; |
altasoul | 0:0547c8bf304f | 26 | |
altasoul | 0:0547c8bf304f | 27 | RTOS_Serial::RTOS_Serial(PinName tx, PinName rx, const char *name) |
altasoul | 0:0547c8bf304f | 28 | : Serial(tx, rx, name) |
altasoul | 0:0547c8bf304f | 29 | { |
altasoul | 0:0547c8bf304f | 30 | const PinName leds[] = {LED1,LED2,LED3,LED4}; |
altasoul | 0:0547c8bf304f | 31 | ledp = new DigitalOut(leds[get_index()]); |
altasoul | 0:0547c8bf304f | 32 | tx_emitter_threadp = new Thread(tx_emitter, (void *) this); |
altasoul | 1:5a66fddad7c4 | 33 | tx_tp[get_index()] = tx_emitter_threadp; |
altasoul | 1:5a66fddad7c4 | 34 | attach(tx_isr[get_index()], Serial::TxIrq); |
altasoul | 1:5a66fddad7c4 | 35 | } |
altasoul | 0:0547c8bf304f | 36 | |
altasoul | 1:5a66fddad7c4 | 37 | serial_t RTOS_Serial::get_serial() { return _serial; } |
altasoul | 0:0547c8bf304f | 38 | |
altasoul | 0:0547c8bf304f | 39 | int RTOS_Serial::get_index() { return _serial.index; } |
altasoul | 0:0547c8bf304f | 40 | |
altasoul | 0:0547c8bf304f | 41 | int RTOS_Serial::putc(int c) { |
altasoul | 0:0547c8bf304f | 42 | //return Serial::putc(c); |
altasoul | 0:0547c8bf304f | 43 | //if (tx_q.put((int *)c, osWaitForever) == osOK) return c; else return EOF; |
altasoul | 0:0547c8bf304f | 44 | int status; |
altasoul | 0:0547c8bf304f | 45 | if ( (status = tx_q.put((int *)c, osWaitForever)) == osOK) return c; else { |
altasoul | 0:0547c8bf304f | 46 | std::printf("tx_q.put() returned %d\r\n", status); |
altasoul | 0:0547c8bf304f | 47 | return EOF; |
altasoul | 0:0547c8bf304f | 48 | } |
altasoul | 0:0547c8bf304f | 49 | } |
altasoul | 0:0547c8bf304f | 50 | |
altasoul | 0:0547c8bf304f | 51 | int RTOS_Serial::parent_putc(int c) { |
altasoul | 0:0547c8bf304f | 52 | return Serial::putc(c); |
altasoul | 0:0547c8bf304f | 53 | } |
altasoul | 0:0547c8bf304f | 54 | |
altasoul | 0:0547c8bf304f | 55 | // class method |
altasoul | 0:0547c8bf304f | 56 | void RTOS_Serial::UART0_TX_ISR(){ |
altasoul | 0:0547c8bf304f | 57 | uint32_t IRR = LPC_UART0->IIR; |
altasoul | 0:0547c8bf304f | 58 | //tx_emitter_threadp->signal_set(0x1); |
altasoul | 0:0547c8bf304f | 59 | tx_tp[0]->signal_set(0x01); |
altasoul | 0:0547c8bf304f | 60 | } |
altasoul | 1:5a66fddad7c4 | 61 | // class method |
altasoul | 1:5a66fddad7c4 | 62 | void RTOS_Serial::UART1_TX_ISR(){ |
altasoul | 1:5a66fddad7c4 | 63 | uint32_t IRR = LPC_UART1->IIR; |
altasoul | 1:5a66fddad7c4 | 64 | //tx_emitter_threadp->signal_set(0x1); |
altasoul | 1:5a66fddad7c4 | 65 | tx_tp[1]->signal_set(0x01); |
altasoul | 1:5a66fddad7c4 | 66 | } |
altasoul | 1:5a66fddad7c4 | 67 | // class method |
altasoul | 1:5a66fddad7c4 | 68 | void RTOS_Serial::UART2_TX_ISR(){ |
altasoul | 1:5a66fddad7c4 | 69 | uint32_t IRR = LPC_UART2->IIR; |
altasoul | 1:5a66fddad7c4 | 70 | //tx_emitter_threadp->signal_set(0x1); |
altasoul | 1:5a66fddad7c4 | 71 | tx_tp[2]->signal_set(0x01); |
altasoul | 1:5a66fddad7c4 | 72 | } |
altasoul | 1:5a66fddad7c4 | 73 | // class method |
altasoul | 1:5a66fddad7c4 | 74 | void RTOS_Serial::UART3_TX_ISR(){ |
altasoul | 1:5a66fddad7c4 | 75 | uint32_t IRR = LPC_UART3->IIR; |
altasoul | 1:5a66fddad7c4 | 76 | //tx_emitter_threadp->signal_set(0x1); |
altasoul | 1:5a66fddad7c4 | 77 | tx_tp[3]->signal_set(0x01); |
altasoul | 1:5a66fddad7c4 | 78 | } |
altasoul | 1:5a66fddad7c4 | 79 | |
altasoul | 1:5a66fddad7c4 | 80 | func RTOS_Serial::tx_isr[4] = { |
altasoul | 1:5a66fddad7c4 | 81 | &RTOS_Serial::UART0_TX_ISR, |
altasoul | 1:5a66fddad7c4 | 82 | &RTOS_Serial::UART1_TX_ISR, |
altasoul | 1:5a66fddad7c4 | 83 | &RTOS_Serial::UART2_TX_ISR, |
altasoul | 1:5a66fddad7c4 | 84 | &RTOS_Serial::UART3_TX_ISR, |
altasoul | 1:5a66fddad7c4 | 85 | }; |
altasoul | 1:5a66fddad7c4 | 86 | |
altasoul | 1:5a66fddad7c4 | 87 | Thread* RTOS_Serial::tx_tp[4] = { NULL, NULL, NULL, NULL }; |
altasoul | 0:0547c8bf304f | 88 | |
altasoul | 0:0547c8bf304f | 89 | // tx_emitter is a class method |
altasoul | 0:0547c8bf304f | 90 | void RTOS_Serial::tx_emitter(void const *argument){ |
altasoul | 0:0547c8bf304f | 91 | RTOS_Serial *sp = (RTOS_Serial *) argument; |
altasoul | 0:0547c8bf304f | 92 | osEvent evt; |
altasoul | 0:0547c8bf304f | 93 | while(true){ |
altasoul | 0:0547c8bf304f | 94 | #if 0 |
altasoul | 0:0547c8bf304f | 95 | *(sp->ledp) = 0; |
altasoul | 0:0547c8bf304f | 96 | osDelay(200); |
altasoul | 0:0547c8bf304f | 97 | *(sp->ledp) = 1; |
altasoul | 0:0547c8bf304f | 98 | osDelay(200); |
altasoul | 0:0547c8bf304f | 99 | #endif |
altasoul | 0:0547c8bf304f | 100 | #if 1 |
altasoul | 0:0547c8bf304f | 101 | evt = sp->tx_q.get(); |
altasoul | 0:0547c8bf304f | 102 | if (evt.status == osEventMessage) { |
altasoul | 1:5a66fddad7c4 | 103 | Thread::signal_wait(0x1); |
altasoul | 0:0547c8bf304f | 104 | *(sp->ledp) = 1; |
altasoul | 0:0547c8bf304f | 105 | sp->parent_putc(evt.value.v); |
altasoul | 0:0547c8bf304f | 106 | *(sp->ledp) = 0; |
altasoul | 0:0547c8bf304f | 107 | } else { |
altasoul | 0:0547c8bf304f | 108 | std::printf("tx_emitter() evt.status %d\n", evt.status); |
altasoul | 0:0547c8bf304f | 109 | } |
altasoul | 0:0547c8bf304f | 110 | #endif |
altasoul | 0:0547c8bf304f | 111 | *(sp->ledp) = 0; |
altasoul | 0:0547c8bf304f | 112 | } |
altasoul | 0:0547c8bf304f | 113 | } |