Serial Wire Output (SWO) viewer for tracing purposes. Tested on F401 and ST-LINK Utility as well as for F103 and Segger J-Link SWO viewer.
Dependents: WiFi_Scanner mbed_nucleo_swo DISCO-F429ZI_LCDTS_demo_richard TEST_SM_SPEED
SWO.cpp
- Committer:
- wim
- Date:
- 2014-12-20
- Revision:
- 1:bae4cff278f6
- Parent:
- 0:0fd55660fc26
- Child:
- 2:ef928f61a770
File content as of revision 1:bae4cff278f6:
/* mbed SWO Library * Copyright (c) 2014, v01: WH. Ported from Segger example * * Simple implementation for tracing via Single Wire Output(SWO) for Cortex-M processors. * It can be used with Host PC software such as ST-LINK Utility or Segger J-Link SWO viewer. * This sample implementation ensures that output via SWO is enabled in order to guarantee * that the application does not hang. * * 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 "SWO.h" /** * * Defines for Cortex-M debug unit */ #define ITM_STIM_U32(n) (*(volatile unsigned int*)(0xE0000000+4*n)) // Stimulus Port n Register word access #define ITM_STIM_U8(n) (*(volatile char*)(0xE0000000+n)) // Stimulus Port n Register byte access //#define ITM_STIM_U32_0 (*(volatile unsigned int*)0xE0000000) // Stimulus Port 0 Register word access //#define ITM_STIM_U8_0 (*(volatile char*)0xE0000000) // Stimulus Port 0 Register byte access #define ITM_ENA (*(volatile unsigned int*)0xE0000E00) // Trace Enable Ports Register #define ITM_TCR (*(volatile unsigned int*)0xE0000E80) // Trace control register /** * * SWO_PrintChar() * * @brief * Checks if SWO is set up. If it is not, return, * to avoid program hangs if no debugger is connected. * If it is set up, print a character to the ITM_STIM register * in order to provide data for SWO. * @param c The Character to be printed. * @notes Additional checks for device specific registers can be added. */ void SWO_PrintChar(char c) { // Check if ITM_TCR.ITMENA is set if ((ITM_TCR & 1) == 0) { return; } // Check if stimulus port is enabled if ((ITM_ENA & 1) == 0) { return; } // Wait until STIMx FIFO is ready, then send data while ((ITM_STIM_U8(0) & 1) == 0); ITM_STIM_U8(0) = c; // while ((ITM_STIM_U32(0) & 1) == 0); // ITM_STIM_U32(0) = c; } /** * * SWO_PrintString() * * @brief Print a string via SWO. * @param *s The string to be printed. * */ void SWO_PrintString(const char *s) { // Print out characters until \0 while (*s) { SWO_PrintChar(*s++); } }