开源pyOCD的使用介绍

ID:351097 · 发表于 2020-8-23 22:26

本帖最后由没有你于 2020-8-23 22:39 编辑

pyOCD是一个开源Python软件包，用于使用多种受支持的USB调试探针类型来编程和调试Arm Cortex-M微控制器。它是完全跨平台的，并支持Linux，macOS和Windows。它内置支持多达70种流行的MCU。另外，通过使用CMSIS-Pack，几乎支持市场上的所有Cortex-M设备。pyOCD还可以作为GDB Service配合GDB调试芯片，支持多种探针，比如：CMSIS-DAP v1(HID)、CMSIS-DAP v2(WinUSB)、SEGGER J-Link、ST-LINK v2和ST-LINK v3。 pyOCD其实和openOCD功能类似，也是支持跨平台的。pyOCD允许用户通过命令来：烧录、擦除、单步、停止、设置断点、全速运行、芯片上锁、读写外设寄存器、读写存储空间等操作。不过网上对pyOCD的教程介绍比较少，不像openOCD那么多，增加了学习的难度。我索性花了半天的时间研究了一下，现在把我所知道的总结一下，希望对后来学习pyOCD的人有所帮助。如果有转载的需要，请务必标注出处。学习的同时也要时时刻刻分享，分享的同时，自己也会有所提升。
我的操作系统是64位的Win10，python的版本为3.8.3，pyOCD的版本为0.27.2，探针是DAP-LINK(CMSIS-DAP v2），单片机是stm32f103rc。下面的所有操作都是基于这个环境完成。
一、pyOCD的安装
pyOCD是一个python库，可用通过pip install pyocd就会自动安装pyOCD以及其依赖库。其中依赖库有：cmsis-pack-manger、intelhex、pyusb、pywinusb、pyelftools、pyyaml、six、pylink-square、prettytable、colorame和interbaltree。一般pip会去外网下库，速度很慢。我们可用借助国内的pip镜像网站下载。比如

pip install -i https://pypi.tuna.tsinghua.edu.cn/simpl pyocd

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速度就比较快了。安装完毕之后，可用查看pyOCD版本：

C:\Users\86188\Desktop> pyocd --version
0.27.2

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二、查看pyOCD的帮助信息
如果你是第一次接触pyOCD并且什么都不知道，那么查看帮助文档是个好建议。可用输入如下命令查看帮助信息：

C:\Users\86188\Desktop> pyocd --help
usage: pyocd [-h] [-V] [--help-options] ...
PyOCD debug tools for Arm Cortex devices
optional arguments:
-h, --help show this help message and exit
-V, --version show program's version number and exit
--help-options Display available user options.
subcommands:
commander Interactive command console.
cmd Alias for 'commander'.
erase Erase entire device flash or specified sectors.
flash Program an image to device flash.
reset Reset a device.
gdbserver Run the gdb remote server(s).
gdb Alias for 'gdbserver'.
json Output information as JSON.
list List information about probes, targets, or boards.
pack Manage CMSIS-Packs for target support.

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通过subcommand知道，pyOCD的子命令有cmd、erase、flash、reset、gdb、json、list和pack。下面对这些命令作简要的介绍。
三、擦除命令erase
输入帮助命令可以查看到如下信息：

C:\Users\86188\Desktop> pyocd erase --help
usage: pyocd erase [-h] [-v] [-q] [-j PATH] [--config PATH] [--no-config] [--script PATH] [-O OPTION=VALUE]
[-da DAPARG [DAPARG ...]] [--pack PATH] [-u UNIQUE_ID] [-b BOARD] [-t TARGET] [-f FREQUENCY] [-W]
[-M MODE] [-c] [-s] [--mass]
[<sector-address> [<sector-address> ...]]
optional arguments:
-h, --help show this help message and exit
-v, --verbose More logging. Can be specified multiple times.
-q, --quiet Less logging. Can be specified multiple times.
configuration:
-j PATH, --dir PATH Set the project directory. Defaults to the directory where pyocd was run.
--config PATH Specify YAML configuration file. Default is pyocd.yaml or pyocd.yml.
--no-config Do not use a configuration file.
--script PATH Use the specified user script. Defaults to pyocd_user.py.
-O OPTION=VALUE Set named option.
-da DAPARG [DAPARG ...], --daparg DAPARG [DAPARG ...]
Send setting to DAPAccess layer.
--pack PATH Path to a CMSIS Device Family Pack.
connection:
-u UNIQUE_ID, --uid UNIQUE_ID, --probe UNIQUE_ID
Choose a probe by its unique ID or a substring thereof.
-b BOARD, --board BOARD
Set the board type (not yet implemented).
-t TARGET, --target TARGET
Set the target type.
-f FREQUENCY, --frequency FREQUENCY
SWD/JTAG clock frequency in Hz. Accepts a float or int with optional case-insensitive K/M
suffix and optional Hz. Examples: "1000", "2.5khz", "10m".
-W, --no-wait Do not wait for a probe to be connected if none are available.
-M MODE, --connect MODE
Select connect mode from one of (halt, pre-reset, under-reset, attach).
erase options:
-c, --chip Perform a chip erase.
-s, --sector Erase the sectors listed as positional arguments.
--mass Perform a mass erase. On some devices this is different than a chip erase.
<sector-address> List of sector addresses or ranges to erase.
If no position arguments are listed, then no action will be taken unless the --chip or --mass-erase options are
provided. Otherwise, the positional arguments should be the addresses of flash sectors or address ranges. The end
address of a range is exclusive, meaning that it will not be erased. Thus, you should specify the address of the
sector after the last one to be erased. If a '+' is used instead of '-' in a range, this indicates that the second
value is a length rather than end address. Examples: 0x1000 (erase single sector starting at 0x1000) 0x800-0x2000
(erase sectors starting at 0x800 up to but not including 0x2000) 0+8192 (erase 8 kB starting at address 0)

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这个帮助信息里面有几个信息：usage、optional argument、configuration、connection、erase options。usage是基本使用方法介绍，里面详细标注pyocd erase可以带哪些类型的参数；optional argument是一些帮助信息等；configuration是一些配置信息，比如工程路径、软件包路径等信息；connection是一些连接的信息，比如探针ID、板对象、目标对象、SWD/JTAG通信频率和连接模式等信息；erase options是擦除相关的参数，里面有chip（擦除全部存储空间）、sector（擦除程序使用的空间）、mass。最简单的命令要包含connection和erase option，也就是操作对象的操作方法。下面列举一些擦除的操作：

擦除全部存储空间
pyocd erase --chip --target stm32f103rc
擦除程序使用的空间
pyocd erase --sector --target stm32f103rc
mass擦除
pyocd erase --mass --target stm32f103rc

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虽然可以用-c代替--chip，-t代替--target，也就是pyocd erase -c -t stm32f103rc。看起来简洁很多，但是这种非常不具备可读性，不建议这样干。下面是操作的执行结果：

C:\Users\86188\Desktop\test> pyocd erase --chip --target stm32f103rc
0001520:INFO:eraser:Erasing chip...
0001612:INFO:eraser:Done

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四、烧录命令flash
输入帮助命令可以查看到如下信息：

C:\Users\86188\Desktop\test> pyocd flash --help
usage: pyocd flash [-h] [-v] [-q] [-j PATH] [--config PATH] [--no-config] [--script PATH] [-O OPTION=VALUE]
[-da DAPARG [DAPARG ...]] [--pack PATH] [-u UNIQUE_ID] [-b BOARD] [-t TARGET] [-f FREQUENCY] [-W]
[-M MODE] [-e {auto,chip,sector}] [-a ADDR] [--trust-crc] [--format {bin,hex,elf}] [--skip BYTES]
PATH
optional arguments:
-h, --help show this help message and exit
-v, --verbose More logging. Can be specified multiple times.
-q, --quiet Less logging. Can be specified multiple times.
configuration:
-j PATH, --dir PATH Set the project directory. Defaults to the directory where pyocd was run.
--config PATH Specify YAML configuration file. Default is pyocd.yaml or pyocd.yml.
--no-config Do not use a configuration file.
--script PATH Use the specified user script. Defaults to pyocd_user.py.
-O OPTION=VALUE Set named option.
-da DAPARG [DAPARG ...], --daparg DAPARG [DAPARG ...]
Send setting to DAPAccess layer.
--pack PATH Path to a CMSIS Device Family Pack.
connection:
-u UNIQUE_ID, --uid UNIQUE_ID, --probe UNIQUE_ID
Choose a probe by its unique ID or a substring thereof.
-b BOARD, --board BOARD
Set the board type (not yet implemented).
-t TARGET, --target TARGET
Set the target type.
-f FREQUENCY, --frequency FREQUENCY
SWD/JTAG clock frequency in Hz. Accepts a float or int with optional case-insensitive K/M
suffix and optional Hz. Examples: "1000", "2.5khz", "10m".
-W, --no-wait Do not wait for a probe to be connected if none are available.
-M MODE, --connect MODE
Select connect mode from one of (halt, pre-reset, under-reset, attach).
flash options:
-e {auto,chip,sector}, --erase {auto,chip,sector}
Choose flash erase method. Default is sector.
-a ADDR, --base-address ADDR
Base address used for the address where to flash a binary. Defaults to start of flash.
--trust-crc Use only the CRC of each page to determine if it already has the same data.
--format {bin,hex,elf}
File format. Default is to use the file's extension.
--skip BYTES Skip programming the first N bytes. This can only be used with binary files.
PATH File to program into flash.

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通过flash options知道可以烧录三种格式的文件：hex、bin和elf，其中bin和elf不带地址信息，需要在参数指定烧录起始地址。下面列举一些烧录的操作：

不擦除芯片，单纯烧录hex
pyocd flash --target stm32f103rc template.hex
先擦除，再烧录hex
pyocd flash --erase chip --target stm32f103rc template.hex
先擦除，再烧录bin，指定起始地址为0x8000000
pyocd flash -erase chip --target stm32f103rc --base-address 0x8000000 template.bin

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一般烧录前需要擦除要烧录的区域，因为ROM的特性，只能通过擦除才能写1。下面是操作的执行结果：

C:\Users\86188\Desktop\test> pyocd flash --erase chip --target stm32f103rc template.hex
[====================] 100%
0002818:INFO:loader:Erased chip, programmed 10240 bytes (5 pages), skipped 0 bytes (0 pages) at 13.31 kB/s

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五、复位命令reset
输入帮助命令可以查看到如下信息：

C:\Users\86188\Desktop\test> pyocd reset --help
usage: pyocd reset [-h] [-v] [-q] [-j PATH] [--config PATH] [--no-config] [--script PATH] [-O OPTION=VALUE]
[-da DAPARG [DAPARG ...]] [--pack PATH] [-u UNIQUE_ID] [-b BOARD] [-t TARGET] [-f FREQUENCY] [-W]
[-M MODE] [-m METHOD]
optional arguments:
-h, --help show this help message and exit
-v, --verbose More logging. Can be specified multiple times.
-q, --quiet Less logging. Can be specified multiple times.
configuration:
-j PATH, --dir PATH Set the project directory. Defaults to the directory where pyocd was run.
--config PATH Specify YAML configuration file. Default is pyocd.yaml or pyocd.yml.
--no-config Do not use a configuration file.
--script PATH Use the specified user script. Defaults to pyocd_user.py.
-O OPTION=VALUE Set named option.
-da DAPARG [DAPARG ...], --daparg DAPARG [DAPARG ...]
Send setting to DAPAccess layer.
--pack PATH Path to a CMSIS Device Family Pack.
connection:
-u UNIQUE_ID, --uid UNIQUE_ID, --probe UNIQUE_ID
Choose a probe by its unique ID or a substring thereof.
-b BOARD, --board BOARD
Set the board type (not yet implemented).
-t TARGET, --target TARGET
Set the target type.
-f FREQUENCY, --frequency FREQUENCY
SWD/JTAG clock frequency in Hz. Accepts a float or int with optional case-insensitive K/M
suffix and optional Hz. Examples: "1000", "2.5khz", "10m".
-W, --no-wait Do not wait for a probe to be connected if none are available.
-M MODE, --connect MODE
Select connect mode from one of (halt, pre-reset, under-reset, attach).
reset options:
-m METHOD, --method METHOD
Reset method to use ('hw', 'sw', and others). Default is 'hw'.

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从reset options知道复位有2种方式：sw（软复位）、hw（硬复位），区别就是hw是通过拉低目标芯片的reset引脚来让芯片产生硬件复位。下面列举一些复位的操作：

软复位
pyocd reset --method sw --target stm32f103rc
硬复位
pyocd reset -method hw --target stm32f103rc

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下面是操作的执行结果：

C:\Users\86188\Desktop\test> pyocd reset --method sw --target stm32f103rc

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六、列表命令list
输入帮助命令可以查看到如下信息：

C:\Users\86188\Desktop\test> pyocd list --help
usage: pyocd list [-h] [-v] [-q] [-j PATH] [--config PATH] [--no-config] [--script PATH] [-O OPTION=VALUE]
[-da DAPARG [DAPARG ...]] [--pack PATH] [-p] [-t] [-b] [-n NAME] [-r VENDOR] [-s {builtin,pack}]
[-H]
optional arguments:
-h, --help show this help message and exit
-v, --verbose More logging. Can be specified multiple times.
-q, --quiet Less logging. Can be specified multiple times.
configuration:
-j PATH, --dir PATH Set the project directory. Defaults to the directory where pyocd was run.
--config PATH Specify YAML configuration file. Default is pyocd.yaml or pyocd.yml.
--no-config Do not use a configuration file.
--script PATH Use the specified user script. Defaults to pyocd_user.py.
-O OPTION=VALUE Set named option.
-da DAPARG [DAPARG ...], --daparg DAPARG [DAPARG ...]
Send setting to DAPAccess layer.
--pack PATH Path to a CMSIS Device Family Pack.
list output:
-p, --probes List available probes.
-t, --targets List all known targets.
-b, --boards List all known boards.
list options:
-n NAME, --name NAME Restrict listing to items matching the given name. Applies to targets and boards.
-r VENDOR, --vendor VENDOR
Restrict listing to items whose vendor matches the given name. Applies to targets.
-s {builtin,pack}, --source {builtin,pack}
Restrict listing to targets from the specified source. Applies to targets.
-H, --no-header Don't print a table header.

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下面列举一些list的操作：

列出可用的探针
pyocd list --probes
列出所有支持的目标板
pyocd list --targets
列出所有支持的开发板
pyocd list --boards

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下面是操作结果

C:\Users\86188\Desktop\test> pyocd list --probes
# Probe Unique ID
--------------------------------------------------------------------------------------
0 NUCLEO-F103RB [stm32f103rb] 07000001066bff303631544157112037a5a5a5a597969908

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每个探针都有唯一的ID，如果有多个探针连接到PC，可以通过ID来确定要操作那个探针连接的开发板。下面是pyOCD内置支持的芯片。

C:\Users\86188\Desktop\test> pyocd list --targets
Name Vendor Part Number Families Source
-----------------------------------------------------------------------------------------------------
cc3220sf Texas Instruments CC3220SF builtin
cortex_m Generic CoreSightTarget builtin
cy8c64_sysap Cypress cy8c64_sysap builtin
cy8c64x5_cm0 Cypress cy8c64x5_cm0 builtin
cy8c64x5_cm0_full_flash Cypress cy8c64x5_cm0_full_flash builtin
cy8c64x5_cm4 Cypress cy8c64x5_cm4 builtin
cy8c64x5_cm4_full_flash Cypress cy8c64x5_cm4_full_flash builtin
cy8c64xa_cm0 Cypress cy8c64xA_cm0 builtin
cy8c64xa_cm0_full_flash Cypress cy8c64xA_cm0_full_flash builtin
cy8c64xa_cm4 Cypress cy8c64xA_cm4 builtin
cy8c64xa_cm4_full_flash Cypress cy8c64xA_cm4_full_flash builtin
cy8c64xx_cm0 Cypress cy8c64xx_cm0 builtin
cy8c64xx_cm0_full_flash Cypress cy8c64xx_cm0_full_flash builtin
cy8c64xx_cm0_nosmif Cypress cy8c64xx_cm0_nosmif builtin
cy8c64xx_cm0_s25hx512t Cypress cy8c64xx_cm0_s25hx512t builtin
cy8c64xx_cm4 Cypress cy8c64xx_cm4 builtin
cy8c64xx_cm4_full_flash Cypress cy8c64xx_cm4_full_flash builtin
cy8c64xx_cm4_nosmif Cypress cy8c64xx_cm4_nosmif builtin
cy8c64xx_cm4_s25hx512t Cypress cy8c64xx_cm4_s25hx512t builtin
cy8c6xx5 Cypress CY8C6xx5 builtin
cy8c6xx7 Cypress CY8C6xx7 builtin
cy8c6xx7_nosmif Cypress CY8C6xx7_nosmif builtin
cy8c6xx7_s25fs512s Cypress CY8C6xx7_S25FS512S builtin
cy8c6xxa Cypress CY8C6xxA builtin
hc32f003 HDSC HC32F003 builtin
hc32f005 HDSC HC32F005 builtin
hc32f030 HDSC HC32F030 builtin
hc32f072 HDSC HC32F072 builtin
hc32f120x6 HDSC HC32F120x6TA builtin
hc32f120x8 HDSC HC32F120x8TA builtin
hc32f190 HDSC HC32F190 builtin
hc32f196 HDSC HC32F196 builtin
hc32f46x HDSC HC32F46x builtin
hc32l072 HDSC HC32L072 builtin
hc32l073 HDSC HC32L073 builtin
hc32l110 HDSC HC32L110 builtin
hc32l130 HDSC HC32L130 builtin
hc32l136 HDSC HC32L136 builtin
hc32l190 HDSC HC32L190 builtin
hc32l196 HDSC HC32L196 builtin
hc32m120 HDSC HC32M120 builtin
k20d50m NXP K20D50M builtin
k22f NXP K22F builtin
k22fa12 NXP K22FA12 builtin
k28f15 NXP K28F15 builtin
k32l2b3 NXP K32L2B3 builtin
k32w042s NXP K32W042S builtin
k64f NXP K64F builtin
k66f18 NXP K66F18 builtin
k82f25615 NXP K82F25615 builtin
ke15z7 NXP KE15Z7 builtin
ke18f16 NXP KE18F16 builtin
kinetis NXP Kinetis builtin
kl02z NXP KL02Z builtin
kl05z NXP KL05Z builtin
kl25z NXP KL25Z builtin
kl26z NXP KL26Z builtin
kl27z4 NXP KL27Z4 builtin
kl28z NXP KL28x builtin
kl43z4 NXP KL43Z4 builtin
kl46z NXP KL46Z builtin
kl82z7 NXP KL82Z7 builtin
kv10z7 NXP KV10Z7 builtin
kv11z7 NXP KV11Z7 builtin
kw01z4 NXP KW01Z4 builtin
kw24d5 NXP KW24D5 builtin
kw36z4 NXP KW36Z4 builtin
kw40z4 NXP KW40Z4 builtin
kw41z4 NXP KW41Z4 builtin
lpc11u24 NXP LPC11U24 builtin
lpc11xx_32 NXP LPC11XX_32 builtin
lpc1768 NXP LPC1768 builtin
lpc4088 NXP LPC4088 builtin
lpc4088dm NXP LPC4088dm builtin
lpc4088qsb NXP LPC4088qsb builtin
lpc4330 NXP LPC4330 builtin
lpc54114 NXP LPC54114 builtin
lpc54608 NXP LPC54608 builtin
lpc55s28 NXP LPC55S28 builtin
lpc55s69 NXP LPC55S69 builtin
lpc800 NXP LPC800 builtin
lpc824 NXP LPC824 builtin
m252kg6ae Nuvoton M252KG6AE builtin
m263kiaae Nuvoton M263KIAAE builtin
max32600 Maxim MAX32600 builtin
max32620 Maxim MAX32620 builtin
max32625 Maxim MAX32625 builtin
max32630 Maxim MAX32630 builtin
mimxrt1010 NXP MIMXRT1011xxxxx builtin
mimxrt1015 NXP MIMXRT1015xxxxx builtin
mimxrt1020 NXP MIMXRT1021xxxxx builtin
mimxrt1050 NXP MIMXRT1052xxxxB_hyperflash builtin
mimxrt1050_hyperflash NXP MIMXRT1052xxxxB_hyperflash builtin
mimxrt1050_quadspi NXP MIMXRT1052xxxxB_quadspi builtin
mps3_an522 Arm AN522 builtin
mps3_an540 Arm AN540 builtin
musca_a1 Arm MuscaA1 builtin
musca_b1 Arm MuscaB1 builtin
ncs36510 ONSemiconductor NCS36510 builtin
nrf51 Nordic Semiconductor NRF51 builtin
nrf52 Nordic Semiconductor NRF52832 builtin
nrf52840 Nordic Semiconductor NRF52840 builtin
rtl8195am Realtek Semiconductor RTL8195AM builtin
s5js100 Samsung S5JS100 builtin
stm32f051 STMicroelectronics STM32F051 builtin
stm32f103rc STMicroelectronics STM32F103RC builtin
stm32f412xe STMicroelectronics STM32F412xE builtin
stm32f412xg STMicroelectronics STM32F412xG builtin
stm32f429xg STMicroelectronics STM32F429xG builtin
stm32f429xi STMicroelectronics STM32F429xI builtin
stm32f439xg STMicroelectronics STM32F439xG builtin
stm32f439xi STMicroelectronics STM32F439xI builtin
stm32f767zi STMicroelectronics STM32F767xx builtin
stm32l031x6 STMicroelectronics STM32L031x6 builtin
stm32l475xc STMicroelectronics STM32L475xC builtin
stm32l475xe STMicroelectronics STM32L475xE builtin
stm32l475xg STMicroelectronics STM32L475xG builtin
w7500 WIZnet W7500 builtin

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七、json命令
输入帮助命令可以查看到如下信息：

C:\Users\86188\Desktop\test> pyocd json --help
usage: pyocd json [-h] [-j PATH] [--config PATH] [--no-config] [--script PATH] [-O OPTION=VALUE]
[-da DAPARG [DAPARG ...]] [--pack PATH] [-p] [-t] [-b] [-f]
optional arguments:
-h, --help show this help message and exit
configuration:
-j PATH, --dir PATH Set the project directory. Defaults to the directory where pyocd was run.
--config PATH Specify YAML configuration file. Default is pyocd.yaml or pyocd.yml.
--no-config Do not use a configuration file.
--script PATH Use the specified user script. Defaults to pyocd_user.py.
-O OPTION=VALUE Set named option.
-da DAPARG [DAPARG ...], --daparg DAPARG [DAPARG ...]
Send setting to DAPAccess layer.
--pack PATH Path to a CMSIS Device Family Pack.
json output:
-p, --probes List available probes.
-t, --targets List all known targets.
-b, --boards List all known boards.
-f, --features List available features and options.

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json命令和list命令的功能差不多，只不过json命令的数据输出格式是按照标准的json格式。下面列举一些json的操作：

以json格式列出可用的探针
pyocd json --probes
以json格式列出所有支持的目标板
pyocd json --targets
以json格式列出所有支持的开发板
pyocd json --boards
以json格式列出所有支持的开发板
pyocd json --features

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下面是一些执行结果：

C:\Users\86188\Desktop\test> pyocd json --targets
{
"pyocd_version": "0.27.2",
"version": {
"major": 1,
"minor": 2
},
"status": 0,
"targets": [
{
"name": "mps3_an522",
"vendor": "Arm",
"part_families": [],
"part_number": "AN522",
"source": "builtin"
},
{
"name": "mps3_an540",
"vendor": "Arm",
"part_families": [],
"part_number": "AN540",
"source": "builtin"
},
{
"name": "cortex_m",
"vendor": "Generic",
"part_families": [],
"part_number": "CoreSightTarget",
"source": "builtin"
},

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八、软件包命令pack
输入帮助命令可以查看到如下信息：

C:\Users\86188\Desktop\test> pyocd pack --help
usage: pyocd pack [-h] [-v] [-q] [-c] [-u] [-s] [-f GLOB] [-i GLOB] [-n] [-H]
optional arguments:
-h, --help show this help message and exit
-v, --verbose More logging. Can be specified multiple times.
-q, --quiet Less logging. Can be specified multiple times.
pack operations:
-c, --clean Erase all stored pack information.
-u, --update Update the pack index.
-s, --show Show the list of installed packs.
-f GLOB, --find GLOB Report pack(s) in the index containing matching device part numbers.
-i GLOB, --install GLOB
Download and install pack(s) containing matching device part numbers.
pack options:
-n, --no-download Just list the pack(s) that would be downloaded, don't actually download anything.
-H, --no-header Don't print a table header.

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这个是软件包的管理操作命令，可以显示软件包的信息也可以下载软件包。但是实际上，下载软件包的时候总是出现服务器没有响应的情况，估计是服务器不在国内。所以这个功能还是比较鸡肋的，幸好pyOCD内置支持不少芯片。
如果芯片刚好不是内置支持的芯片，那就需要自己找对于的软件包。比如芯片是gd32f103c8，可以自己去找GigaDevice.GD32F10x_DFP.2.0.2.pack，然后使用的时候带上--pack参数指定pack包的路径即可。比如下面操作：

pyocd flash --erase chip --target gd32f103c8 --pack=./GigaDevice.GD32F10x_DFP.2.0.2.pack template.hex

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九、cmd命令
输入帮助命令可以查看到如下信息：

<blockquote>C:\Users\86188\Desktop> pyocd cmd --help

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从commander options，可以知道--halt这个命令被标记为弃用，也就是不建议使用。--command命令里面有其他操作，可以输入帮助信息查看：

C:\Users\86188\Desktop\test> pyocd cmd --command help
Commands:
--------
break ADDR Set a breakpoint address
cmp, compare ADDR [LEN] FILENAME Compare a memory range against a binary file.
core [NUM] Select CPU core by number or print selected core
d, disasm [-c/--center] ADDR [LEN] Disassemble instructions at an address
erase [ADDR] [COUNT] Erase internal flash sectors (performs mass erase if no arguments given)
exit, quit Quit pyocd-tool
fill [SIZE] ADDR LEN PATTERN Fill a range of memory with a pattern
find ADDR LEN BYTE... Search for a value in memory within the given address range.
gdbserver ACTION Start or stop the gdbserver.
c, continue, g, go Resume execution of the target
h, halt Halt the target
?, help [CMD] Show help for commands
initdp Init DP and power up debug.
list Show available targets
load FILENAME [ADDR] Load a binary, hex, or elf file with optional base address
loadmem ADDR FILENAME Load a binary file to an address in memory (RAM or flash)
lsbreak List breakpoints
lswatch List watchpoints
makeap APSEL Creates a new AP object for the given APSEL.
r16, read16, rh ADDR [LEN] Read 16-bit halfwords
r32, read32, rw ADDR [LEN] Read 32-bit words
r, rb, read, read8 ADDR [LEN] Read 8-bit bytes
rap, readap [APSEL] ADDR Read AP register
rdp, readdp ADDR Read DP register
reg [-f] [REG] Print core or peripheral register(s).
reinit Reinitialize the target object
reset [-h/--halt] Reset the target
rmbreak ADDR Remove a breakpoint
rmwatch ADDR Remove a watchpoint
savemem ADDR LEN FILENAME Save a range of memory to a binary file
set NAME VALUE Set an option value
show INFO Report info about the target
st, stat, status Show the target's current state
s, step Step one instruction
symbol NAME Show a symbol's value.
unlock Unlock security on the target
watch ADDR [r|w|rw] [1|2|4] Set a watchpoint address, and optional access type (default rw) and size (4).
where [ADDR] Show symbol, file, and line for address.
wreg [-r] REG VALUE Set the value of a core or peripheral register.
w16, wh, write16 ADDR DATA... Write 16-bit halfwords to memory (RAM or flash). The address may be unaligned. Flash writes are subject to minimum write size and alignment.
w32, write32, ww ADDR DATA... Write 32-bit words to memory (RAM or flash). The address may be unaligned. Flash writes are subject to minimum write size and alignment.
w, wb, write, write8 ADDR DATA... Write 8-bit bytes to memory (RAM or flash). Flash writes are subject to minimum write size and alignment.
wap, writeap [APSEL] ADDR DATA Write AP register
wdp, writedp ADDR DATA Write DP register
All register names are also available as commands that print the register's value.
Any ADDR or LEN argument will accept a register name.
Prefix line with $ to execute a Python expression.
Prefix line with ! to execute a shell command.
Info:
----
cores Information about CPU cores in the target.
fault Fault status information.
graph Print the target object graph.
hnonsec Display the current HNONSEC value used by the selected MEM-AP.
hprot Display the current HPROT value used by the selected MEM-AP.
locked Report whether the target is locked.
map Target memory map.
mem-ap Display the currently selected MEM-AP used for memory read/write commands.
nreset Current nRESET signal state.
option Show the current value of one or more user options.
peripherals List of target peripheral instances.
si, step-into-interrupt Display whether interrupts are enabled when single stepping.
target General target information.
uid Target's unique ID
vc, vector-catch Show current vector catch settings.
Options:
-------
clock Set SWD or JTAG clock frequency in Hertz. A case-insensitive metric scale suffix of either 'k' or 'm' is allowed, as well as a trailing "Hz". There must be no space between the frequency and the suffix. For example, "2.5MHz" sets the clock to 2.5 MHz.
hnonsec Set the current HNONSEC value used by the selected MEM-AP.
hprot Set the current HPROT value used by the selected MEM-AP.
log Set log level to one of debug, info, warning, error, critical
mem-ap Select the MEM-AP used for memory read/write commands.
nreset Set nRESET signal state. Accepts a value of 0 or 1.
option Change the value of one or more user options.
si, step-into-interrupt Set whether to enable or disable interrupts when single stepping. Set to 1 to enable.
vc, vector-catch Control enabled vector catch sources.

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这里面的指令就比较多了，都是一些芯片调试相关的。下面列举一些操作：

加载hex文件
pyocd cmd --command load template.hex --target stm32f103rc
复位芯片
pyocd cmd --command reset --target stm32f103rc
擦除芯片
pyocd cmd --command erase --target stm32f103rc
芯片暂停（然后就可用操作单步、打断点等）
pyocd cmd --connect halt --target stm32f103rc
设置断点
pyocd cmd --command break 0x0800029e --target stm32f103rc
单步运行
pyocd cmd --command step --target stm32f103rc
恢复执行
pyocd cmd --command go --target stm32f103rc
查询芯片当前状态
pyocd cmd --command status --target stm32f103rc
读取4个字节
pyocd cmd --command read32 0x40010c00 12 --connect attach --target stm32f103rc
打印内核或者外设寄存器
pyocd cmd --command reg --connect attach --target stm32f103rc

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这些指令主要是电脑端GDB和pyOCD的GDB Service交互用的。当然自己也可以试着调试，一般调试都要先让芯片halt（暂停），然后才能插入断点、单步、读写寄存器、读写内存等操作。下面是一些简单的调试过程：

C:\Users\86188\Desktop\test> pyocd cmd --command load template.hex --target stm32f103rc
[====================] 100%
PS C:\Users\86188\Desktop\test> pyocd cmd --connect halt --target stm32f103rc
Connected to STM32F103RC [Halted]: 07000001066bff303631544157112037a5a5a5a597969908
pyocd> step
PC = 0x080015de
pyocd> step
PC = 0x080004ce
pyocd> break 0x080004ce
Set breakpoint at 0x080004ce
pyocd> status
Core 0: Halted
pyocd> reg
r0: 0x080004cf r6: 0x00000000 r12: 0x00000001
r1: 0x40022000 r7: 0x00000000 sp: 0x20001788
r2: 0x00000001 r8: 0x00000000 lr: 0x080015e1
r3: 0x7a6a5aa8 r9: 0x20000200 pc: 0x080004ce
r4: 0x00000000 r10: 0x08002504 xpsr: 0x01000000
r5: 0x20001124 r11: 0x00000000 primask: 0x00000000
pyocd> go
Device is halted; a debug event may have occurred
pyocd> lsbreak
5 hardware breakpoints available
0: 0x080004ce
pyocd> rmbreak 0x080004ce
Removed breakpoint at 0x080004ce
pyocd> go
Successfully resumed device
pyocd> status
Core 0: Running
pyocd>

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先把程序load到芯片，然后让芯片halt下来，再单步、打断点、查看芯片状态、查看寄存器、查看断点、移除断点、全速运行、查看状态。一般用keil或者IAR，只需要点击几个图案就能完成芯片调试的操作，只能说明keil太方便了。这里是纯粹用命令行控制，虽然难度增加了不少，但是对调试器的原理和功能会多点认识，这就是进步吧。后面再配合GDB，就能用GDB的方式调试代码了。
本来这篇介绍应该在下午完成，但是出了点意外。我习惯在51平台网页在线编辑，一不小心按了ctrl+A+Delete，全部删了。想要撤销操作，按了ctrl+Z，居然不支持，更坑的地方是网页默认30秒保存，当时就剩下几秒时间，来不及操作，就被覆盖保存。点击恢复，出现自动保存的空白页面。急忙联系网站负责人，还是没有找回资料。白白浪费了3个小时。没办法晚上再花了3个半小时，重新码字，总算完成。这个经历给了一个教训：一定要在本地保存！
如果感觉这篇介绍对你有帮助，请支持一下。有任何疑问，欢迎留言讨论！