CAN bus configuration and terminal resistance
CAN bus configuration is a key step in CCP 521 debugging. Each CAN bus station must be assigned a unique station number, up to a maximum of 31 stations can be installed, and each station number can only be assigned once. The data transmission rate (baud rate) can be set according to the length of the bus, and the longer the bus, the lower the baud rate. The corresponding relationship is: code 00 is 615 kBit/s, maximum length 60 m; 01 is 500 kBit/s, 80 m; 02 is 250 kBit/s, 160 m; 03 is 125 kBit/s, 320 m; 04 is 100 kBit/s, 400 m; 05 is 50 kBit/s, 800 m; 06 is 20 kBit/s, 1200 m; 07 is 1 Mbit/s, 30 m. These values apply to 120 Ω twisted pair cables. In the CAN bus protocol, 1 kBit/s equals 1 kBaud.
In the CAN bus system, both end modules must be terminal matched to avoid transmission errors caused by line reflections. If CCP 521 is a terminal module, a 150 Ω resistor can be placed between CAN-A (Low) and CAN-B (High) for termination. During actual wiring, it should be confirmed that the bus topology is linear to avoid excessively long star shaped branches; Confirm that the shielding layer is well grounded; Confirm that all nodes have consistent baud rates; Confirm that there is no conflict with the station number. If communication is unstable, prioritize checking terminal resistance, cable shielding, and grounding.
Status display and 7-segment digital tube
CCP 521 is equipped with a 2-digit decimal 7-segment digital display for displaying configuration parameters, error messages, and system variable _cpuDisplay during program execution. When configuring the processor module, the parameters are displayed on the digital display. If an error occurs during program execution or a valid user program is not found, the display will alternate between "Er" (error) and error code. The same error code will also be displayed in the LASAL status line. When the program is running, the system variable _cpuDisplay can display values from 0 to 255, but values exceeding 99 are not displayed and the digital display remains dark.
The status LED includes Ethernet, VARAN, and control LED. The Ethernet Active yellow light lights up during Ethernet data exchange, and the Link green light lights up when two PHY connections are established. The yellow light of VARAN Active lights up during data exchange on the VARAN bus, and the green light of Link lights up when two PHY connections are established. In the control LED, the ERROR red light lights up when an error occurs (such as a USV fault), and the DCOK green light lights up when the power supply is normal. These indicator lights are first-hand information for quickly determining the status of the module on site.
Detailed explanation of system startup checkpoints and error codes
When the system starts, the 7-segment digital display will show checkpoints. Checkpoints appear before LASAL CLASS software status and error messages. If the system stops at a checkpoint, it should be interpreted as an error. For example, displaying "88" indicates that the system is starting up; If the status does not change, it indicates that the operating system or application cannot start. Possible reasons include: incomplete startup of the operating system, checking of the operating system/boot media, failure to insert the boot media, damaged boot media, absence of an operating system on the boot media, BIOS self-test errors, RAM/CPU/BIOS issues, etc.
The status and error messages are displayed in the status test of LASAL CLASS software, and the CPU status display will also show the status or error number. Common error codes include: 00 RUN RAM (user program running in RAM), 01 RUN ROM (user program loaded into RAM and running in program memory), 02 RUNTIME (total duration of all loop objects exceeds maximum time, configurable through Runtime and SWRuntime system variables), 03 POINT ER (incorrect program pointer detected before running user program, possible reasons include program memory module missing, unprogrammed or damaged, program not executable, user program overwriting software error), 04 CHKSUM (invalid checksum detected before running user program, processed with POINT ER), 05 Watchdog (program interrupted by watchdog logic, possible reasons include interrupt being blocked for a long time, hardware interrupt programming error), The sentence is: Inappropriate use of INB/OUTB/INW/OUTW instructions, processor defects), 06 GENERAL (general error), 07 PROM DEFECT (program memory module defect, user program too large, program memory module missing), 08 Reset (CPU receives reset signal, waiting for further instructions, user program not processing), 09 WD DEFEKT (hardware monitoring circuit defect, CPU needs to be replaced), 10 STOP, 11 PROG BUSYS, 12 GRAM LENGTH, 13 PROG END (memory module successfully completed), 14 PROG MEMO (CPU programming memory module), 15 STOP BRKPT (CPU stopped by breakpoint), 16 CPU STOP (CPU stopped by PG software) 17 INT ERROR (CPU triggers error interrupt or encounters unknown instruction, possible reasons include using non-existent operating system, stack error, user program interrupted by software error), 18 SINGLE STEP (CPU in single step mode), 19 Ready (module or item sent to CPU, ready to run), 20 LOAD (program stopped, receiving module or item), 21 UNZUL. Module DIAS bus error, check DIAS bus and terminal resistance), 26 WAIT (CPU busy), 27 OP PROG (operating system being reprogrammed), 28 OP INSTALLED (operating system reinstalled), 29 OS TOO LONG (operating system unable to load, memory too small), 30 NO Operating SYSTEM (boot loader message), Operating system not found in RAM), 31 SEARCH FOR OS (bootloader searching for operating system in RAM), 32 NO DEVICE, 33 UNUSED CODE, 34 MEM ERROR (loaded operating system does not match hardware configuration), 35 MAX IO, 36 MODULE LOAD ERROR (LASAL module or project cannot be loaded), 37 GENELLER BS-FEHLER (general error occurs when loading operating system), 38 APPLMEM ERROR (error occurs in application memory), 39 OFFLINE, 40 APPL LOAD, 41 APPL SAVE, 44 VARAN MANAGER ERROR (error number stored in VARAN Manager, program execution stops, possible reasons may include actual network and project Mismatch, log file needs to be read), 45 VARAN ERROR (required VARAN Client) Removed or communication error occurs, program execution stops, possible reasons include wiring damage, distributed module lack of power, need to read log files, analyze error tree), 46 APPL-LOAD-ERROR (error loading application), 47 APPL-SAVE-ERROR (error saving application) DIAS Master error), 64 INTERNAL ERROR (internal error, all applications stopped, needs to be restarted and SIGMATEK reported), 65 FILE ERROR( File operation error), 66 DEBUG ASSERTION FAILED (internal error, restart and report), 67 REAL TIME RUNTIME CPU ready to run), 105 C_OR (CPU ready to run), 106 C_UNKNOWN_CID (unknown class, unknown base class), 107 C_UNKNOWN_COSTR( Unable to create operating system class, possible operating system error), 108 C_UNKNOWN_OBECT (referencing unknown object in interpreter program, creating multiple DCC080 objects), 109 C_UNKNOWN.CHNL (hardware module number greater than 60), 110 C_WRONG_CONNECT (no required channel for connection), 111 C_WRONG_ATTR (incorrect server attribute), 112 C_SYNTAX_SERR (no specific error, recompiling and reloading project components), 113 C_NOFILE. OPEN (attempting to open unknown table), 114 C_OUTOF. NEAR (memory allocation error), 115 C_OUT OF. FAR (memory allocation error), 116 C_INCOMPATIBLE (same name object exists) But the classes are different), 117 C_COMPATIBLE (objects of the same name and class exist but must be updated), 224 LINKING (application is linking), 225 LINKING ERROR (linking error), 226 LINKING DON( Link completed), 230 OP BURN (operating system burning to Flash), 231 OP BURN FAIL (error burning operating system), 232 OP INSTALL (operating system installing), 240 USV-WAIT (power off, UPS activated), 241 Reboot (operating system reboot), 242 LSL SAVE, 243 LSL LOAD, 252 Continuation, 253 PRERUN (application startup), 254 PRERESET (application end), 255 CONNECTION BREAK.