
R
XCR3032C: 32 Macrocell CPLD with Enhanced Clocking
7
www.xilinx.com
1-800-255-7778
DS040 (v1.3) October 9, 2000
This product has been discontinued. Please see
for details.3.3V, In-System Programming (ISP)
ISP is the ability to reconfigure the logic and functionality of
a device, printed circuit board, or complete electronic sys-
tem before, during, and after its manufacture and shipment
to the end customer. ISP provides substantial benefits in
each of the following areas:
Design
-
Faster time-to-market
-
Debug partitioning and simplified prototyping
-
Printed circuit board reconfiguration during debug
-
Better device and board level testing
Manufacturing
-
Multi-Functional hardware
-
Reconfigurability for test
-
Eliminates handling of
“
fine lead-pitch
”
components
for programming
-
Reduced Inventory and manufacturing costs
-
Field Support
-
Easy remote upgrades and repair
-
Support for field configuration, re-configuration, and
customization
Improved quality and reliability
The Xilinx XCR3032C allows for 3.3V in-system program-
ming/reprogramming of its EEPROM cells via its JTAG
interface. An on-chip charge pump eliminates the need for
externally-provided supervoltages, so that the XCR3032C
may be easily programmed on the circuit board using only
the 3.3V supply required by the device for normal opera-
tion. A set of low-level ISP basic commands implemented
in the XCR3032C enable this feature. The ISP commands
implemented in the Xilinx XCR3032C are specified in
Table 5
. Please note that an ENABLE command must pre-
cede all ISP commands
unless
an ENABLE command has
already been given for a preceding ISP command.
Table 2: XCR3032C Low-Level JTAG Boundary-Scan Commands
Instruction
(Instruction Code)
Register Used
Bypass
(1111)
Bypass Register
Description
Places the 1 bit bypass register between the TDI and TDO pins, which allows the BST
data to pass synchronously through the selected device to adjacent devices during nor-
mal device operation. The Bypass instruction can be entered by holding TDI at a constant
high value and completing an Instruction-Scan cycle.
Selects the IDCODE register and places it between TDI and TDO, allowing the IDCODE
to be serially shifted out of TDO. The IDCODE instruction permits blind interrogation of
the components assembled onto a printed circuit board. Thus, in circumstances where
the component population may vary, it is possible to determine what components exist in
a product.
Idcode
(0001)
Boundary-Scan Register
Table 3: JTAG Pin Description
Pin
TCK
Name
Description
Test Clock Output
Clock pin to shift the serial data and instructions in and out of the TDI and TDO pins, re-
spectively.
Serial input pin selects the JTAG instruction mode. TMS should be driven high during user
mode operation.
Serial input pin for instructions and test data. Data is shifted in on the rising edge of TCK.
Serial output pin for instructions and test data. Data is shifted out on the falling edge of
TCK. The signal is 3-stated if data is not being shifted out of the device.
TMS
Test Mode Select
TDI
TDO
Test Data Input
Test Data Output
Table 4: XCR3032C JTAG Pinout by Package Type
Device
XCR3032C
44-pin PLCC
44-pin VQFP
(Pin Number / Macrocell #)
TMS
13/A8
7/A8
TCK
32/B8
26/B8
TDI
7/A3
1/A3
TDO
38/B3
32/B3