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Download MC68360 QUad Integrated Communications Controller User`s Manual
Transcript
Freescale Semiconductor, Inc. CPU32+ Operand Data: A single operand is data to be written to the memory location. Byte data is transmitted as a 16-bit word, justified in the least significant byte; 16- and 32-bit operands are transmitted as 16 and 32 bits, respectively. Result Data: Status is returned as in the WRITE command: $0FFFF for a successful operation and $10001 for a bus or address error during write. Freescale Semiconductor, Inc... 5.6.2.8.12 Resume Execution (GO). The pipeline is flushed and refilled before normal instruction execution is resumed. Prefetching begins at the return PC and current privilege level. If either the PC or SR is altered during BDM, the updated value of these registers is used when prefetching commences. NOTE The processor exits BDM when a bus error or address error occurs on the first instruction prefetch from the new PC—the error is trapped as a normal mode exception. The stacked value of the current PC may not be valid in this case, depending on the state of the machine prior to entering BDM. For address error, the PC does not reflect the true return PC. Instead, the stacked fault address is the (odd) return PC. Command Format: 15 0 14 0 13 0 12 0 11 1 10 1 9 0 8 0 7 0 6 0 5 0 4 0 3 0 2 0 1 0 0 0 Command Sequence: GO ??? NORMAL MODE XXX "ILLEGAL" NEXT CMD "NOT READY" Operand Data: None Result Data: None 5.6.2.8.13 Call User Code (CALL). This instruction provides a convenient way to patch user code. The return PC is stacked at the location pointed to by the current SP. The stacked PC serves as a return address to be restored by the RTS command that terminates the patch routine. After stacking is complete, the 32-bit operand data is loaded into the PC. The pipeline is flushed and refilled from the location pointed to by the new PC, BDM is exited, and normal mode instruction execution begins. MC68360 USER’S MANUAL For More Information On This Product, Go to: www.freescale.com
