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Page 88 State of XSVF File Implementation The XSVF file sup port has been implemented in accordance with the "XA PP503, App endix B: XSVF File Format" specificat ion available at th e Xilinx website with the fo…

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Notes

Some AVR devices do not support page by page

programming. In such a case, the SVF file must be

created without the -mp parameter.

Lattice CPLD Programming

SVF file can be created from a .JED file using ispVM

System. This program is part of the ispLEVER Classic

system, which is available at the Lattice website.

Altera CPLD Programming

The QUARTUS II program by Altera can generate SVF files

if it is set up so in the menu.

Such an SVF file, however, cannot be used as it is due to

a wrong Silicon ID. According to Altera, SVF files

generated by their software are assumed only for ATE

(Automatic Test Equipment) programmers and Altera

does not consider supporting others.

However, such an SVF file can be manually modified to

suit our needs. In order to do so, delete the "CHECKING

SILICON ID" section in the SVF file or mark it as a non-

executable comment.

State of .svf File

Implementation

The SVF file support has been implemented in accordance

with the "Serial Vector Format Specification, Revision E"

available at

www.asset-intertech.com/support/svf.html

with the following limitations:

• PIO a PIOMAP commands are not implemented.

• HDR+SDR+TDR / HIR+SIR+TIR length is limited to

2^31 bits.

• Supported TCK frequencies are 3MHz, 1.5MHz,

750kHz and fragments of 1MHz starting at 500kHz

for PRESTO. FORTE adds 15MHz, 10MHz and 5MHz

on top of these.

• RUNTEST MAXIMUM max_time SEC parameter is

ignored.

• RUNTEST run_count is limited to 2^31/3

(approximately 715million).

• RUNTEST min_time SEC is limited to 2^31/3ms

(approximately 715seconds).

• TRST and RUNTEST SCK – these commands share the

same configurable P/VPP pin of both the PRESTO and

FORTE programmers and can never be used together.

8.1.2 XSVF File

XSVF (Xilinx Serial Vector Format) is a file used for

describing high-level operations on the IEEE1149.1 bus

extended by Xilinx.

XSVF is recommended for Xilinx CPLD XC9500.

Examples of How to Create

XSVF Files

Xilinx CPLD Programming

To create an XSVF file, use the iMPACT program available

at the Xilinx website.

Choose Prepare Configuration Files ➙ Boundary-

Scan File ➙ XSVF File in the Operation Mode

Selection dialog window that opens after the iMPACT

program starts. Run all operations (Erase, Program,

Verify, Test...) the same way as if a programmer was

connected (e.g. Xilinx Parallel Cable). Then save the new

file and close iMPACT. Running the created XSVF file will

perform the recorded operations.

We do not recommend using an SVF file for

programming devices of the Xilinx XC9500 family, as the

algorithm for XC9500/XL/XV device programming cannot

be correctly described in the SVF format.

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State of XSVF File

Implementation

The XSVF file support has been implemented in

accordance with the "XAPP503, Appendix B: XSVF File

Format" specification available at the Xilinx website with

the following limitations:

• XSETSDRMASKS, XSDRINC and XSIR2 commands are

not implemented.

• Only the XSVF file format is recommended for

programming the Xilinx XC9500/XV/XL families.

We seriously recommend using an SVF file for all

architectures except XC9500/XV/XL. For XC9500/XV/XL

programming, the use of the XSVF format is

recommended as the SVF format does not include the

XREPEAT command, which is necessary for XC9500/XV/XL

programming.

Warning: Executing a file containing the XREPEAT

command may be very slow.

8.1.3 Programming

Connector

The following table describes the functions of PRESTO's

and FORTE's pins for programming by means of the JTAG

interface.

PRESTO

FORTE

Function

VPP

SCK (System Clock)/User defined state

during file execution and after.

Not connected pin (key)

VDD

Feeding of I/O buffers

GND

Ground of I/O buffers

MOSI

JTAG TDI (Test Data In)

CLOCK

JTAG TCK (Test Clock)

MISO

JTAG TDO (Test Data out)

LVP

JTAG TMS (Test Machine State)

Table12: JTAG programming connector

8.2

Settings

This chapter explains the meaning of different settings in

Options ➙ Program Options.

8.2.1 Default TCK signal

frequency

This frequency of the TCK clock is used until the JTAG

Player reaches the first FREQUENCY command in the SVF

file or until the FREQUENCY with the "default" value is

reached.

The XSVF file format does not support the FREQUENCY

default command. Therefore frequency defined by

Default TCK Signal Frequency parameter is applied to

all operations.

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The maximum frequency is 3MHz for the PRESTO

programmer and 15MHz for FORTE.

If the Ignore FREQUENCY commands option is selected,

the programmer applies only the frequency set by the

user and ignores all FREQUENCY commands.

8.2.2 Fast Clocks Option

(FORTE only)

This option is available only for the FORTE programmer.

According to the JTAG specification, the signal at TDI is

sampled at TCK's rising edge. However, should a higher

frequency be required (around 5MHz or more), it may be

useful to change the moment of sampling from the rising

edge to the falling edge by shifting it by 1/2 of the TCK

period. To do so, choose Fast Clock Option.

8.2.3 RUNTEST without

run_count (SVF only)

The programmer should stay in the specified state for the

specified time and generate the clock signal on TCK while

executing an SVF file.

The specified time can be exceeded, but it slows the

programming process down. Even though it is not

supported by the SVF specification, many programmable

devices allow stopping the TCK clock during this time.

The programmer's ability to keep accurate time needs to

be considered. A high level of accuracy cannot be

achieved if the maximum frequency is used (the

programmer can guarantee respecting the min_time SEC

parameter only). A higher accuracy can be achieved with

slow clock (~100kHz). If the clock signal is not used at

all, the programmer is capable of following the min_time

SEC parameter almost exactly.

Three possibilities are available considering these facts:

• no clock on TCK

• slow clock on TCK (~100kHz)

• default speed clock on TCK

Example: "RUNTEST 3E-3SEC;" means "Generate clock on

TCK for at least 3ms".

8.2.4 RUNTEST Timing

Multiply (both SVF

and XSVF)

Recommended values:

• for accurate timing specified in the SVF or XSVF file:

0% (no added time)

• for XC9500(XL) family: 100% or more

• for Atmel AVR (e.g. ATmega128): 25%

8.2.5 RUNTEST with

run_count and no

timing

(bothSVFandXSVF)

This command should be interpreted as the minimum

frequency on TCK.

Yet some SVF file generators (such as Xilinx iMPACT, for

example) use this command as waiting time and assume

a frequency of 1MHz. For such cases the use of "interpret

as RUNTEST min_time with scale 1MHz" setting is

recommended.

JTAG Player Behavior When Reaching RUNTIME

Command With MINTIME Specification

(This concerns only SVF files as the RUNTEST alternative,

which is usable in XSVF XRUNTEST run_count cannot

specify time.)