Register: 0x5a, Register: 0x5b – Avago Technologies LSI53C895A User Manual
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Registers
Register: 0x5A
General Purpose Pin Control One (GPCNTL1)
Read/Write
This register is used to determine if the signals controlled by the General
Purpose One register are inputs or outputs. Bits [3:0] in GPCNTL1
correspond to bits [3:0] in
General Purpose Pin Control One (GPCNTL1)
register. When the bits are enabled as inputs, an internal pull-down is
also enabled. The data written to each bit of the GPREG1 register is
output to the appropriate GPIO pin if it is set to the output mode in this
register.
R
Reserved
[7:4]
GPIOEN[8:5] GPIO Enable
[3:0]
General purpose control, corresponding to bits [3:0] in
the
register. GPIO[8:5]
power-up as general purpose inputs.
Register: 0x5B
General Purpose One (GPREG1)
Read/Write
R
Reserved
[7:4]
GPIO[8:5]
General Purpose I/O
[3:0]
These bits can be programmed through the
Purpose Pin Control One (GPCNTL1)
register to become
inputs or outputs. As outputs, these pins can be used to
enable or disable external terminators. These signals can
also be programmed as live inputs and sensed through a
SCRIPTS register to Register Move instruction.
GPIO[8:5] default as inputs. When configured as inputs,
an internal pull-down is enabled.
7
4
3
0
R
GPIOEN[8:5]
0
x
x
x
1
1
1
1
7
4
3
0
R
GPIO[8:5]
x
x
x
x
x
x
x
x