Renesas SuperH Family E10A-USB - Manual (Page 20)

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3. Low-Power States (Sleep, Software Standby, Module Standby, U Standby, and R Standby)
For low-power consumption, the SH7343 has sleep, software standby, module standby, U
standby, and R standby states.
The sleep, software standby, and module standby states are switched using the SLEEP
instruction. When the emulator is used, the sleep and software standby states can be cleared
with either the normal clearing function or with the [STOP] button, and a break will occur.
Note: The memory must not be accessed or modified in sleep state.
4. Reset Signals
The SH7343 reset signals are only valid during emulation started with clicking the GO or
STEP-type button. If these signals are enabled on the user system in command input wait state,
they are not sent to the SH7343.
Note: Do not break the user program when the /RESETA, /RESETMFI, or /BREQ signal is
being low and the wait control signal is being active. A TIMEOUT error will occur. If
the wait control signal becomes active or the /BREQ signal is fixed to low during break, a
TIMEOUT error will occur at memory access.
5. Direct Memory Access Controller (DMAC)
The DMAC operates even when the emulator is used. When a data transfer request is
generated, the DMAC executes DMA transfer.
6. Memory Access during User Program Execution
When a memory is accessed from the memory window, etc. during user program execution,
the user program is resumed after it has stopped in the E10A-USB emulator to access the
memory. Therefore, realtime emulation cannot be performed.
The stopping time of the user program is as follows:
Environment:
Host computer: 800 MHz (Pentium
® III)
JTAG clock: 10 MHz (TCK clock)
When a one-byte memory is read from the command-line window, the stopping time will be
about 42 ms.
7. Memory Access during User Program Break
The emulator can download the program for the flash memory area (for details, refer to section
6.22, Download Function to the Flash Memory Area, in the SuperH
TM Family E10A-USB
Emulator User’s Manual). Other memory write operations are enabled for the RAM area.
Therefore, an operation such as memory write or BREAKPOINT should be set only for the
RAM area.