The INDEX PORT is used to select
a
Chip - Level (Global) Control/Configuration
Registers[0x00-0x2F]
configuration register in the chip. The DATA
PORT is then used to access the selected
register. These registers are accessable only in
the Configuration Mode.
The chip-level (global) registers lie in the
address range [0x00-0x2F]. The design MUST
use all 8 bits of the ADDRESS Port for register
selection. All unimplemented registers and bits
ignore writes and return zero when read.
Table 76 - Chip - Level Registers
ADDRESS DESCRIPTION
REGISTER
STATE
Chip (Global) Control Registers
0x00 -
0x01
Reserved - Writes are ignored, reads return 0.
Config Control
0x02 W
The hardware automatically clears this bit after the
write; there is no need for software to clear the bits.
Bit 0
C
Default = 0x00
on Vcc POR or
Reset_Drv
= 1: Soft Reset. Refer to the "Configuration
Registers" table for the soft reset value for each
register.
Index Address
0x03 R/W Bit[7]
= 1 Enable GP1, GP2, WDT_CTRL, GP4, GP5,
GP6, GP7, Soft Power and SMI Enable and
Status Register access when not in
configuration mode
Default = 0x03
on Vcc POR or
Reset_Drv
= 0 Disable GP1, GP2, WDT_CTRL, GP4, GP5,
GP6, GP7, Soft Power and SMI Enable and
Status Register access when not in
configuration mode (Default)
Bits [6:2]
Reserved - Writes are ignored, reads return 0.
Bits[1:0]
Sets GP1/GP2 selection register used when in Run
mode (not in Configuration Mode).
= 11
= 10
= 01
= 00
0xEA (Default)
0xE4
0xE2
0xE0
0x04 - 0x06
Reserved - Writes are ignored, reads return 0.
177
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