AR# 1424

Programmers, Data I/O - Unisite Programmers issue "Partial Write Not Supported" error on 1700 devices


Keywords: Unisite, Data I/O, programmer

Unisite programmer issues the following error:

"Partial write not supported by this device."


The Data I/O programmer does not support partial programming of Xilinx serial PROMs devices when used in the conventional manner.

When you try to program a Xilinx PROM XC17xx device, the Unisite programmer by default does NOT allow the user to program the device only up to the length of the bitstream. Say your bit stream is 1000 Bytes long and the PROM can store 2000 bytes. Partially programming the PROM means you want the programmer to output the first 1000 bytes, then stop at the last programmed address.

In the Unisite programming software, there is a field called User Data Size through which you can specify the number of bytes
you want to program the PROM with. There is also a DeviceBlock Size field in which you can specify the maximum number of Blocks or bytes the device can handle.

To work around the partial write problem, you need to set User Data Size equal to Device Block Size to make the Unisite programmer accept the bitstream and program the device. The Data I/O programmer appends an extra 4 bytes of data at ( ) for parity checking.

This is because the Unisite Programmer algorithm appends 4 extra bytes at the end of the array to set the polarity for the PROM.
AR# 1424
Date 10/01/2008
Status Archive
Type General Article