Rainbow Electronics ATF1504ASL - Manual (Page 10)

10
ATF1504AS(L)
0950N–PLD–07/02
Programming
ATF1504AS devices are in-system programmable (ISP) devices utilizing the 4-pin JTAG
protocol. This capability eliminates package handling normally required for programming
and facilitates rapid design iterations and field changes.
Atmel provides ISP hardware and software to allow programming of the ATF1504AS via
the PC. ISP is performed by using either a download cable or a comparable board tester
or a simple microprocessor interface.
To facilitate ISP programming by the Automated Test Equipment (ATE) vendors. Serial
Vector Format (SVF) files can be created by Atmel provided software utilities.
ATF1504AS devices can also be programmed using standard third-party programmers.
With third-party programmer, the JTAG ISP port can be disabled thereby allowing
four additional I/O pins to be used for logic.
Contact your local Atmel representatives or Atmel PLD applications for details.
ISP Programming
Protection
The ATF1504AS has a special feature that locks the device and prevents the inputs and
I/O from driving if the programming process is interrupted for any reason. The inputs
and I/O default to high-Z state during such a condition. In addition the pin-keeper option
preserves the former state during device programming, if this circuit were previously
programmed on the device. This prevents disturbing the operation of other circuits in the
system while the ATF1504AS is being programmed via ISP.
All ATF1504AS devices are initially shipped in the erased state thereby making them
ready to use for ISP.
Note: For more information refer to the “Designing for In-System Programmability with Atmel
CPLDs” application note.