Hugh Shane / Mbed 2 deprecated imu-daq

Read data from an ADIS16355 IMU and write it to the USB port.

Dependencies:   mbed

usb-serial.cpp@0:c6ee363ac724, 2011-08-10 (annotated)

Committer:
yahugh
Date:
Wed Aug 10 21:50:36 2011 +0000
Revision:
0:c6ee363ac724
initial release, still has some problems but might be of interest to others regardless

Who changed what in which revision?

UserRevisionLine numberNew contents of line
yahugh 0:c6ee363ac724 1 #include "mbed.h"
yahugh 0:c6ee363ac724 2 #include "usb-serial.h"
yahugh 0:c6ee363ac724 3
yahugh 0:c6ee363ac724 4 volatile unsigned wp, rp;
yahugh 0:c6ee363ac724 5 static const int outbuf_size = 128;
yahugh 0:c6ee363ac724 6 static const unsigned pointer_mask = 0x007fU;
yahugh 0:c6ee363ac724 7 char usb_outbuf[outbuf_size];
yahugh 0:c6ee363ac724 8 static bool overflow;
yahugh 0:c6ee363ac724 9 DigitalOut mydiag(p22);;
yahugh 0:c6ee363ac724 10
yahugh 0:c6ee363ac724 11 extern "C" static void txReadyISR() __irq {
yahugh 0:c6ee363ac724 12
yahugh 0:c6ee363ac724 13 mydiag = 1;
yahugh 0:c6ee363ac724 14 // If the output buffer has data, copy the head to the UART
yahugh 0:c6ee363ac724 15 if (rp != wp) {
yahugh 0:c6ee363ac724 16 LPC_UART0->THR = usb_outbuf[rp];
yahugh 0:c6ee363ac724 17 rp = (rp+1) & pointer_mask;
yahugh 0:c6ee363ac724 18 }
yahugh 0:c6ee363ac724 19
yahugh 0:c6ee363ac724 20 // If the output buffer is empty, disable the transmit buffer empty
yahugh 0:c6ee363ac724 21 // interrupt
yahugh 0:c6ee363ac724 22 if (rp == wp)
yahugh 0:c6ee363ac724 23 LPC_UART0->IER = 0;
yahugh 0:c6ee363ac724 24
yahugh 0:c6ee363ac724 25
yahugh 0:c6ee363ac724 26 mydiag = 0;
yahugh 0:c6ee363ac724 27 }
yahugh 0:c6ee363ac724 28
yahugh 0:c6ee363ac724 29 void usb_serial_init(void) {
yahugh 0:c6ee363ac724 30
yahugh 0:c6ee363ac724 31 // init the output FIFO
yahugh 0:c6ee363ac724 32 wp = 0; rp = 0;
yahugh 0:c6ee363ac724 33 overflow = false;
yahugh 0:c6ee363ac724 34
yahugh 0:c6ee363ac724 35 // init the serial port
yahugh 0:c6ee363ac724 36 Serial usb_serial(USBTX, USBRX);
yahugh 0:c6ee363ac724 37 usb_serial.baud(/*115200*/230400);
yahugh 0:c6ee363ac724 38 usb_serial.format(8, Serial::None, 1);
yahugh 0:c6ee363ac724 39 LPC_UART0->FCR = 7UL;
yahugh 0:c6ee363ac724 40 NVIC_SetVector(UART0_IRQn, (uint32_t)txReadyISR);
yahugh 0:c6ee363ac724 41 NVIC_EnableIRQ(UART0_IRQn);
yahugh 0:c6ee363ac724 42 LPC_UART0->THR = 0; // this is required to start the interrupts, don't understand why
yahugh 0:c6ee363ac724 43 }
yahugh 0:c6ee363ac724 44
yahugh 0:c6ee363ac724 45 bool usb_serial_putc(char c) {
yahugh 0:c6ee363ac724 46
yahugh 0:c6ee363ac724 47 if (overflow == false) {
yahugh 0:c6ee363ac724 48 usb_outbuf[wp] = c;
yahugh 0:c6ee363ac724 49 LPC_UART0->IER = 0; // ---- critical
yahugh 0:c6ee363ac724 50 wp = (wp+1) & pointer_mask;
yahugh 0:c6ee363ac724 51
yahugh 0:c6ee363ac724 52 if (wp == rp)
yahugh 0:c6ee363ac724 53 overflow = true;
yahugh 0:c6ee363ac724 54 else
yahugh 0:c6ee363ac724 55 overflow = false;
yahugh 0:c6ee363ac724 56
yahugh 0:c6ee363ac724 57 LPC_UART0->IER = 2UL; // ---- \critical
yahugh 0:c6ee363ac724 58 } else {
yahugh 0:c6ee363ac724 59 // reinit the output FIFO
yahugh 0:c6ee363ac724 60 wp = 0; rp = 0;
yahugh 0:c6ee363ac724 61 overflow = false;
yahugh 0:c6ee363ac724 62 }
yahugh 0:c6ee363ac724 63
yahugh 0:c6ee363ac724 64 return overflow;
yahugh 0:c6ee363ac724 65 }