Python 了解简单串行接口编程协议-条形码扫描仪

问题陈述：

我正在尝试构建一个简单的应用程序来读取QR/条形码信息并向用户显示显示（首选C/或Python）

用户将在系统中按下一个键

单击后，应启用条形码触发，并准备好扫描请求的条形码（QR/代码39）

用户扫描成功后，其数据应显示在屏幕上

读取/写入串行数据不是问题。我能做到

对于我正在使用的扫描仪型号，文档位于：

我唯一的困惑是形成帧SSI命令

我看到很多这样的例子。但是，我仍然不能清楚地遵循逻辑

unsigned char ledOn[] = {0x05, 0xE7, 0x04, 0x00, 0x0D, 0x00};
unsigned char SSIBuffer[] = {0x00, 0xC6, 0x04, 0x08, 0x11, 0xEE, 0x01};

以上是我从Stackoverflow（）中获得的一些示例：

通过与上面的扫描仪参考文档进行比较，我对信息进行了解码，以便进一步理解

问题1

在文档中，状态字段涉及4位数据：

    Bit 0: Retransmit
    0 = First transmission
    1 = Subsequent transmission
    Bit 1: Continuation
    0 = Last packet of a multipacket message
    1 = Intermediate packet

我不清楚何时会设置上述位及其影响

问题2

ledOn[] = {0x05, 0xE7, 0x04, 0x00, 0x0D, 0x00};
Length(Byte-1)
Command(Byte-2)( LED_ON)
Decoder(Byte-3)
Status(Byte-4)
LED Selection(Byte-5) //**Don’t know where to get this info**


SSIBuffer[] = {0x00, 0xC6, 0x04, 0x08, 0x11, 0xEE, 0x01};
Length(Byte-1) (Will change the buffer later from 0)
Command(Byte-2) (PARAM_SEND)
Decoder(Byte-3)
Status(Byte-4) – Making barcode to set this config permenanent
BEEP_CODE(Byte-5)
Param_data (Byte-6) (Decode Data Packet Format – ref-pl3307)
Param_value(Byte-7)

再次参考数据表，我看到了（SE3300型号）许多操作模式。我想我应该使用普通解码模式和电平触发模式。我不知道使用“快照模式”有什么好处

最后，如何连接多个命令

例如，如果我需要使用液位触发模式程序，根据数据表，这些步骤包括：

The system is initialized as follows:
    • The host sends the Aim Off command.
    • The host sends the Illumination Off command.
    • The host sends the Acquisition Stop command.
    • The host sends the Barcode Decode mode command.
    • The SE3300 optimizes the image output for bar code decoding.
    • The SE3300 enters standby mode (or low power mode if enabled).
Upon a trigger pull:
    • The host sends the Illumination On command.
    • The SE3300 exits standby mode (or low power mode if enabled).
    • The host sends the Aim On command.
    • The host sends the Acquisition Start command.
    • The SE3300 begins outputting images.
    • The host attempts to decode the images.
Upon a good decode or trigger release:
    • The host sends the Acquisition Stop command.
    • The SE3300 stops outputting images.
    • The host sends the Aim Off command.
    • The host sends the Illumination Off command.
    • The SE3300 enters standby mode (or low power mode if enabled).

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是否有人能指导我使用SSI命令为此形成一个简单流程？

您是否试图从规范中编程？如果规范在线，请链接到该规范。

The system is initialized as follows:
    • The host sends the Aim Off command.
    • The host sends the Illumination Off command.
    • The host sends the Acquisition Stop command.
    • The host sends the Barcode Decode mode command.
    • The SE3300 optimizes the image output for bar code decoding.
    • The SE3300 enters standby mode (or low power mode if enabled).
Upon a trigger pull:
    • The host sends the Illumination On command.
    • The SE3300 exits standby mode (or low power mode if enabled).
    • The host sends the Aim On command.
    • The host sends the Acquisition Start command.
    • The SE3300 begins outputting images.
    • The host attempts to decode the images.
Upon a good decode or trigger release:
    • The host sends the Acquisition Stop command.
    • The SE3300 stops outputting images.
    • The host sends the Aim Off command.
    • The host sends the Illumination Off command.
    • The SE3300 enters standby mode (or low power mode if enabled).