Rainbow Electronics ATF1504ASL - Manual (Page 5)

5
ATF1504AS(L)
0950N–PLD–07/02
Block Diagram
Unused product terms are automatically disabled by the compiler to decrease power
consumption. A security fuse, when programmed, protects the contents of the
ATF1504AS. Two bytes (16 bits) of User Signature are accessible to the user for pur-
poses such as storing project name, part number, revision or date. The User Signature
is accessible regardless of the state of the security fuse.
The ATF1504AS device is an in-system programmable (ISP) device. It uses the indus-
try-standard 4-pin JTAG interface (IEEE Std. 1149.1), and is fully-compliant with JTAG’s
Boundary-scan Description Language (BSDL). ISP allows the device to be programmed
without removing it from the printed circuit board. In addition to simplifying the manufac-
turing flow, ISP also allows design modifications to be made in the field via software.
I/O (MC64)/GCLK3