
December 22, 2003
Document No. 38-12011 Rev. *E
189
CY8C24xxx Preliminary Data Sheet
Global Digital Interconnect (GDI)
14.2
Register Definitions
In the CY8C24xxx PSoC device, the configurable GDI is
used to resynchronize the feedback between two digital
PSoC blocks. This is accomplished by connecting a digital
PSoC block’s output to a global output that has been config-
ured to drive its corresponding global input. The global input
is chosen to drive one of the row inputs. The row input is
configured to synchronize the signal to the device’s 24 MHz
system clock. Finally, the row input is used by the second
digital PSoC block. Because CY8C24xxx devices do not
have the one global-to-many port pin relationship, the utility
of the configurable GDI is reduced.
14.2.1
GDI_O_IN and GDI_E_IN
Registers
The PSoC device has a configurable Global Digital Intercon-
nect (GDI). Using the configuration bits in the GDI_x_IN reg-
isters, a global input net may be configured to drive its
corresponding global output net. For example,
There are a total of 16-bits that control the ability of global
inputs to drive global outputs. These bits are in the
GDI_O_IN and GDI_E_IN registers.
Table 14-3
enumerates
the meaning of each bit position in either of the GDI_O_IN
or GDI_E_IN registers.
For additional information, reference the
GDI_O_IN register
on page 170
and the
GDI_E_IN register on page 171
.
14.2.2
GDI_O_OU and GDI_E_OU
Registers
Additional configuration bits are offered in the GDI_x_OU
registers that allow a global output to drive its corresponding
global input. For example,
There are a total of 16 bits that control the ability of global
outputs to drive global inputs. These bits are in the
GDI_O_OU and GDI_E_OU registers.
Table 14-4
enumer-
ates the meaning of each bit position in either of the
GDI_O_OU or GDI_E_OU registers.
The configurability of the GDI does not allow odd and even
nets or nets with different indexes to be connected. The fol-
lowing are examples of connections that are not possible in
the PSoC devices.
For additional information, reference the
GDI_O_OU regis-
ter on page 172
and the
GDI_E_OU register on page 173
.
Table 14-3. GDI_x_IN Register
GDI_x_IN[0]
0: No connection between GIx[0] to GOx[0]
1: Allow GIx[0] to drive GOx[0]
0: No connection between GIx[1] to GOx[1]
1: Allow GIx[1] to drive GOx[1]
0: No connection between GIx[2] to GOx[2]
1: Allow GIx[2] to drive GOx[2]
0: No connection between GIx[3] to GOx[3]
1: Allow GIx[3] to drive GOx[3]
0: No connection between GIx[4] to GOx[4]
1: Allow GIx[4] to drive GOx[4]
0: No connection between GIx[5] to GOx[5]
1: Allow GIx[5] to drive GOx[5]
0: No connection between GIx[6] to GOx[6]
1: Allow GIx[6] to drive GOx[6]
0: No connection between GIx[7] to GOx[7]
1: Allow GIx[7] to drive GOx[7]
GDI_x_IN[1]
GDI_x_IN[2]
GDI_x_IN[3]
GDI_x_IN[4]
GDI_x_IN[5]
GDI_x_IN[6]
GDI_x_IN[7]
GIE
7
[ ]
GOE
7
[ ]
→
Table 14-4. GDI_x_OU Register
GDI_x_OU[0]
0: No connection between GIx[0] to GOx[0]
1: Allow GOx[0] to drive GIx[0]
0: No connection between GIx[1] to GOx[1]
1: Allow GOx[1] to drive GIx[1]
0: No connection between GIx[2] to GOx[2]
1: Allow GOx[2] to drive GIx[2]
0: No connection between GIx[3] to GOx[3]
1: Allow GOx[3] to drive GIx[3]
0: No connection between GIx[4] to GOx[4]
1: Allow GOx[4] to drive GIx[4]
0: No connection between GIx[0] to GOx[5]
1: Allow GOx[5] to drive GIx[5]
0: No connection between GIx[6] to GOx[6]
1: Allow GOx[6] to drive GIx[6]
0: No connection between GIx[7] to GOx[7]
1: Allow GOx[7] to drive GIx[7]
GDI_x_OU[1]
GDI_x_OU[2]
GDI_x_OU[3]
GDI_x_OU[4]
GDI_x_OU[5]
GDI_x_OU[6]
GDI_x_OU[7]
GOE
7
[ ]
GIE
7
[ ]
→
GOE
7
[ ]
GOE
0
[ ]
GIO
7
[ ]
GIE
7
→
→
[ ]