![](http://datasheet.mmic.net.cn/330000/MB90P224BPF_datasheet_16438137/MB90P224BPF_7.png)
7
MB90220 Series
Pin no.
* :FPT-120P-M03, FPT-120C-C02
(Continued)
Pin name
Circuit
type
Function
QFP*
12 to 16
INT3 to INT7
C
External interrupt request input pins
When external interrupts are enabled, these inputs may be used
suddenly at any time; therefore, it is necessary to stop output by other
functions on these pins, except when using them for output
deliberately.
78
P50
C
General-purpose I/O port
This function is valid in single-chip mode and when the CLK output
specification is disabled.
CLK
CLK output pin
This function is valid in modes where the external bus is enabled and
the CLK output specification is enabled.
79
P51
C
General-purpose I/O port
This function is valid in single-chip mode or when the ready function
is disabled.
RDY
Ready input pin
This function is valid in modes where the external bus is enabled and
the ready function is enabled.
80
P52
C
General-purpose I/O port
This function is valid in single-chip mode or when the hold function is
disabled.
HAK
Hold acknowledge output pin
This function is valid in modes where the external bus is enabled and
the hold function is enabled.
81
P53
C
General-purpose I/O port
This function is valid in single-chip mode or external bus mode and
when the hold function is disabled.
HRQ
Hold request input pin
This function is valid in modes where the external bus is enabled and
the hold function is enabled.
During this operation, the input may be used suddenly at any time;
therefore, it is necessary to stop output by other fuctions on this pin,
except when using it for output deliberately.
82
P54
C
General-purpose I/O port
This function is valid in single-chip mode, when the external bus is in
8-bit mode, or when WRH pin output is disabled.
WRH
Write strobe output pin for the high-order 8 bits of the data bus
This function is valid in modes where the external bus is enabled, the
external bus is in 16-bit mode, and WRH pin output is enabled.
83
P55
C
General-purpose I/O port
This function is valid in single-chip mode or when WRL pin output is
disabled.
WRL
Write strobe output pin for the low-order 8 bits of the data bus
This function is valid in modes where the external bus is enabled and
WRL pin output is enabled.