Contributed by Thomas Fischl: add support for USBasp.

patch #4686: Add support for USBasp, a simple USB programmer
* usbasp.c: New file, implement the USBasp driver.
* usbasp.h: New file, interface declarations for USBasp.
* Makefile.am: Wire the new files into the build.
* avrdude.conf.in: Add the usbasp programmer entry.
* config_gram.y: Add the usbasp token.
* lexer.l: (Ditto.)
* avrdude.1: Document the USBasp programmer.
* doc/avrdude.texi: (Ditto.)


git-svn-id: svn://svn.savannah.nongnu.org/avrdude/trunk/avrdude@656 81a1dc3b-b13d-400b-aceb-764788c761c2

avrdude.1

@@ -19,7 +19,7 @@
 .\"
 .\" $Id$
 .\"
-.Dd DATE September 6, 2006
+.Dd DATE September 10, 2006
 .Os
 .Dt AVRDUDE 1
 .Sh NAME
@@ -113,6 +113,12 @@ Atmel's JTAG ICE (both mkI and mkII) is supported as well to up- or download mem
 areas from/to an AVR target (no support for on-chip debugging).
 For the JTAG ICE mkII, both JTAG and ISP mode are supported.
 .Pp
+The USBasp ISP adapter is also supported, provided
+.Nm avrdude
+has been compiled with libusb support.
+It features a simple firwmare-only USB implementation, running on
+an ATmega8 (or ATmega88).
+.Pp
 Input files can be provided, and output files can be written in
 different file formats, such as raw binary files containing the data
 to download to the chip, Intel hex format, or Motorola S-record
@@ -757,3 +763,7 @@ Page-mode programming the EEPROM through JTAG (i.e. through an
 option) requires a prior chip erase.
 This is an inherent feature of the way JTAG EEPROM programming works.
 This also applies to the STK500 in parallel programming mode.
+.Pp
+The USBasp driver does not offer any option to distinguish multiple
+devices connected simultaneously, so effectively only a single device
+is supported.