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The RAM Write Data register enables testing of trace memory connectivity to the TMC. When in Disabled state, a write to this register stores data at the location pointed to by the RWP/RWPHI registers. When not in Disabled state, writes are ignored. When the memory data width, as indicated by the DEVID.MEM_WIDTH register field, is greater than 32 bits, multiple writes to this register must be performed together to write a full memory width of data. For example, if the memory width is 128 bits, then writes to this register must be performed 4 at a time. When a full memory width of data has been written to this register, the data is written to the trace memory and the RWP is incremented to the next memory word. When the STS.MemErr bit is set, writing to this register returns an error response on the APB interface and the write data is discarded.
The RWD register characteristics are:
The following figure shows the bit assignments.
The following table shows the bit assignments.
Table 9-383 RWD register bit assignments
Data written to this register is placed in the trace memory.