Standard Test and Programming Language

JAM / STAPL ("Standard Test and Programming Language") is an Altera-developed standard for JTAG in-circuit programming of programmable logic devices which is defined by JEDEC standard JESD-71.
STAPL defines a standard ".jam" file format which supports in-system programmability or configuration of programmable devices. A JTAG device programmer implements a "JAM player" which reads the file as a set of instructions directing it to program a PLD.
The standard is supported by multiple PLD and device programmer manufacturers.