When using 16M crystal oscillator, the read/write cycle time of the 82C200 is 230ns, and the effective time of the read/write control signal must be greater than 170ns. The wait cycle is inserted in the port operation of the DSP, and the value of the address index register is first latched by the normal DSP read and write operation. , then write or read the value of the data register. To generate an ALE width (>35ns) and RD, WR signal width (>170ns) that meet the 82C200 timing requirements, the ISWS value of the DSP internal wait state generator control register should be greater than 3. Insert 3 wait cycles when reading and writing the port. When the Fclkout1=20MHz of the DSP, the effective level width of the DSPRD and DSPWR of the DSP is extended to 175ns (>170ns); the ALE signal of the 82C200 is DSPWR, IS and DSPA0- DSPA3 decoding is generated, it must be >35ns; at the same time, the read data of 82C200 is 10ns after DSPRD failure, and will not cause bus conflict; while the write data duration of DSP is >25ns, which satisfies the data after 82C200 write signal failure. The retention time should be >23 ns. Comprehensive analysis, after adding 3 waiting cycles, can fully realize the timing coordination of DSP 82C200, and the operation is simple. DSP Interpolation Communication Module Software Design The DSP interpolation communication module acts as a communication intermediary between the industrial computer and the CANBus sub-node, and mainly performs interpolation calculation and data uploading tasks. Programming in a modular way, with the hardware system of the DSP interpolation communication module to achieve the established tasks.
The software structure divides task scheduling management, command checking, interpolation calculation, and CANBus information management into four parts according to tasks. The task scheduling management is the core module of the software, and the execution of other tasks is scheduled according to the priority; the command checking module is a resident task module, which is established during system initialization, has a lower priority, and is obtained by querying the command area of ​​the DPRAM to obtain the IPC. The command performs the corresponding operation; the interpolation calculation module is a higher priority conditional execution module. When the interpolation calculation is allowed and the interpolation buffer is empty, the module acquires data from the interpretation result buffer in the DPRAM, and processes The result is placed in the send message buffer and waiting to be sent to the lower computer. CANBus information management is divided into two parts: receiving information processing and sending information processing, which are responsible for receiving and transmitting information on CANBus. After receiving the node information packet, the CAN controller generates an interrupt to the DSP, and the interrupt processing program fills the information packet into the receiving information queue, and the receiving processing program processes one by one; at the same time, the interpolation data, the PLC information, and the operation instruction that need to be transmitted are The sending handlers are arranged according to the priority of the information, and are sent in sequence. The interpolated communication module adopts a fast and cost-effective DSP chip, and realizes data exchange with the industrial computer through the dual port RAM. Compared with the system implemented by the 51 series and 96 series single chip microcomputers, the speed is fast, the structure is simple, and the function is complete. In the numerical control system, the application can effectively improve the speed and reliability of the information transmission of the upper and lower position machines.
(Finish)
Hard Cover Graphic Novel Printing
Hard Cover Graphic Novel Printing,Hardcover Graphic Novels Printninjia Printing,Hardcover Graphic Novels Mixam Printing,Hardcover Comics Printninjia Printing
Gold Union Printing , https://www.goldunionprinting.com