Resetting - Hitachi SH7751 Hardware Manual

Superh risc engine
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22.5

Resetting

This section describes the resetting supported by the PCIC.
Power-On Reset when Host: A reset (
 
host. The
pin is asserted when a power-on reset is generated at the
software reset is generated by setting 1 in the
control register (PCICR).
Reset Input in Non-Host Mode: The PCIC has no dedicated reset input pin. A reset signal from
the PCI bus can be connected to the
SH7751/SH7751R, but the following point must be noted:
In the PCI standard, the reset (
time required for the power-on reset of the SH7751/SH7751R (see section 23, Electrical
Characteristics), and design the timing of power-on resets so that it satisfies the conditions of the
reset period for both.
Manual Reset: The PCIC does not support the input of manual reset signals via the
No initialization therefore occurs by manual resets.
Software Reset: Software resets are generated by setting 1 in the
(RSTCTL) of the PCI control register (PCICR). The
the PCIC is reset. While a software reset is asserted, the PCIC registers cannot be accessed.
Assertion requires a minimum of 1ms. Software resets are canceled by setting a 0 to the RSTCTL
bit.
It is not possible to set 0 in the RSTCTL bit and set other bits of the PCICR at the same time.
After setting 0 in the RSTCTL bit, set other bits of the PCICR.
Note that not all PCIC registers are reset at a software reset. See section 22.2, PCIC Register
Descriptions, for details of which registers are reset. Use software clears as required for any
registers that are not cleared by the software reset.
Note that, since software resets cannot be asserted while the PCI bus clock is stopped, software
resets must be asserted when the PCI bus clock (PCICLK or CKIO) is being input.
Note that data cannot be guaranteed if a software reset is used while a data transfer is in progress.
 
) can be output to the PCI bus when the PCIC is
 

pin and a power-on reset applied to the
 
signal must be asserted for a minimum of 1msec, check the
output control bit (RSTCTL) of the PCI
 
 
pin is asserted at the same time as
Rev. 3.0, 04/02, page 919 of 1064

pin or when a

pin.
output control bit

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