FEAL60852A-02
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Semiconductor
ML60852A
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5.
OTHER FUNCTIONS
The other functions of the ML60852A are described in this chapter.
5.1.
5EP Mode and 6EP Mode
The ML60852A is provided with two EP modes.
If D2 of the SYSCON register at address 2Fh is set to "0", the 6EP mode is entered. If D2 of the
SYSCON register is set to "1", the 5EP mode is entered.
In 5EP mode, EP0 to EP4 are available. In 6EP mode, EP0 to EP5 are available.
When EP4 is used for isochronous transfer in 5EP mode, the FIFO of EP4 is switched to a 512-byte
two-layer configuration.
When EP4/EP5 is used for isochronous transfer in 6EP mode, the FIFO of EP4/EP5 is switched to a
256-byte two-layer configuration.
5.2.
System Reset
The ML60852A has the functions of hardware reset and software reset as methods of carrying out a
system reset.
The hardware reset is initiated by making active the –RESET pin of the ML60852A.
The same purpose can also be achieved by a software reset which is that of carrying out a system reset
by writing a “1” into D0 of the system control register (SYSCON) at address 2Fh. The hardware reset
and the software reset are functionally identical.
5.3.
Self-powered and Bus-powered
The ML60852A supports both Self-powered and Bus-powered operation.
If the ML60852A is used in the Bus-powered mode, the low-power mode should be selected during the
suspend state.
If D1 of the SYSCON register at address 2Fh is set to “1”, the ML60852A stops oscillation in the
suspend state and enters the low-power state.
For the low-power mode during the suspend state, see Section 5.4 “Suspend Function”.
5.4.
Suspend Function
The ML60852A goes into the suspend state when the idle state in which there is no bus activity on the
USB bus, continues for 3 ms or more.
If D3 of the register INTENBL2 at address 25h has already been set to “1”, when the ML60852A
detects an idle state for 3 ms or longer, D3 of the register INTSTAT2 at address 22h is set to “1” and –
INTR becomes active. The suspend state interrupt allows the local MCU to start processing for
suppressing power consumption. (See Chapter 5 “INTERRUPTS”.)
The ML60852A has a function to suppress power consumption during suspend state. If bit D1 of
register SYSCON at address 2Fh is preset to “1”, the ML60852A will stop oscillation 2 ms after a
suspended state interrupt is caused. When D1 of register SYSCON is “0”, oscillation will not stop even
if the suspend state is entered
See Section 7.1.7.4 “Suspending” or Section 9.1.1.6 “Suspended” in the USB Standard Rev.1.1 for
details of the suspend function.
