Introduction
Opcode 0x01: Write/Read Virtual Register
This command allows the host to access the contents of any of the four virtual registers. The specific operation and register to be accessed are determined by the command options field.
Write data is contained in the Command data field. Read data is returned in the result field.
Command option bits affect the operation as follows:
❏Bit 15 indicates read (0) or write (1) operation
5 |
❏Bit 14 indicates whether to access either the lower half (0) or upper half (1) of the virtual register.
❏Bit 11 & 12 specify which virtual register is to be accessed (0b00 = VR0, 0b01 = VR1, 0b10 = VR2, 0b11 = VR3).
This command cannot fail and will never set the ERR flag in the command/response register
Opcode 0x02: Initialize Memory
This command allows the host to initialize areas of local RAM to a specific value without incurring the overhead of writing each location via the write memory command.
The command options field is unused and must contain 0.
The lower 8 bits of the data field contain the byte pattern to be written.
Memory starting at the address contained in VR0 and the byte count contained in VR1 is initialized with the value contained in the lower 8 bits of the Data field.
Note This command does not guarantee that the memory is initialized using any particular ordering or alignment. Do not use it to initialize any area of memory that has alignment or ordering requirements (e.g., device registers).
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