RTL detects a packet and performs LED on/off based on command bytes in packet. It has a serial TX/RX bus to communicate. It drives RX with TX bytes after link_stable is achieved(Align Markers detection). Send 5 successive AMs to assert link_stable. Files uses Synopsys VCS to compile and simulate.
Byte Encodings: - AM = 0x55, SOP = 0xFB, EOP = 0xFD, IDLE = 0x07
Acronyms: - AM = Align Marker, SOP = Start of Packet, EOP = End of Packet, IDLE = Characters sent when there's no packet transmission
Packet Format: - IDLE | SOP | ID | LENGTH | COMMAND | EOP
COMMAND Ecoding: - LED0 ON = 0x00, LED0 OFF = 0x01, LED1 ON = 0x10, LED1 OFF = 0x11
ID is a configurable parameter in RTL. Packet will only get acted upon by the RTL if the ID in packet matches with the RTL ID. RTL will not send anything on rx_serial till link_stable. 2 RTLs are connected in daisy chain. Minimum length of packet should be 1 otherwise it will lead to error.
COMPILE: vcs -lca -timescale=1ns/100ps -sverilog +verilog2001ext+.v -ntb_opts uvm-1.2 +define+WAVES_FSDB -kdb -debug_access+all -l custom_serial_protocol_compile.log -f custom_serial_protocol_tb_files.f -top custom_serial_protocol_top
SIMULATE: ./simv +vcs+lic+wait -l custom_serial_protocol_sim.log +UVM_MAX_QUIT_COUNT=10000 +UVM_LOG_RECORD +UVM_TR_RECORD +ntb_random_seed=6546 +UVM_VERBOSITY=UVM_MEDIUM