FreeCalypso > hg > freecalypso-sw

annotate target-utils/libprintf/README @ 1031:6312f684cef1

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
gsm-fw feature tch-reroute: byte order changed to big endian
author Mychaela Falconia <falcon@freecalypso.org>
date Tue, 31 May 2016 18:50:32 +0000
parents 40f607bb0a2c
children
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
rev   line source
3
45bf8af5f061 libprintf brought in from older PPC/m68k code, but fucking GCC
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
diff changeset
1 The present libprintf is a very light printf implementation that is well-suited
45bf8af5f061 libprintf brought in from older PPC/m68k code, but fucking GCC
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
diff changeset
2 for simple bare-metal programs like loadagent; in the present case it overrides
45bf8af5f061 libprintf brought in from older PPC/m68k code, but fucking GCC
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
diff changeset
3 the much heavier printf implementation in newlib. Programs like the present
45bf8af5f061 libprintf brought in from older PPC/m68k code, but fucking GCC
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
diff changeset
4 loadagent only need printf in order to scribble on the serial console port,
45bf8af5f061 libprintf brought in from older PPC/m68k code, but fucking GCC
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
diff changeset
5 and the most sensible implementation is to have the "character output" function
45bf8af5f061 libprintf brought in from older PPC/m68k code, but fucking GCC
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
diff changeset
6 from the guts of printf point directly to the physical UART output routine, or
45bf8af5f061 libprintf brought in from older PPC/m68k code, but fucking GCC
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
diff changeset
7 a trivial wrapper that turns \n into \r\n. In contrast, newlib's version would
45bf8af5f061 libprintf brought in from older PPC/m68k code, but fucking GCC
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
diff changeset
8 pull in the complete FILE table infrastructure and malloc etc - maybe OK for
45bf8af5f061 libprintf brought in from older PPC/m68k code, but fucking GCC
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
diff changeset
9 more complex embedded programs that use those facilities for other things under
45bf8af5f061 libprintf brought in from older PPC/m68k code, but fucking GCC
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
diff changeset
10 a bona fide RTOS, but it would be disgusting to pull that stuff in for a
45bf8af5f061 libprintf brought in from older PPC/m68k code, but fucking GCC
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
diff changeset
11 minimal program like ours.
45bf8af5f061 libprintf brought in from older PPC/m68k code, but fucking GCC
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
diff changeset
12
45bf8af5f061 libprintf brought in from older PPC/m68k code, but fucking GCC
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
diff changeset
13 The present printf implementation has been used earlier by the same author
45bf8af5f061 libprintf brought in from older PPC/m68k code, but fucking GCC
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
diff changeset
14 (Michael Spacefalcon) in the StarMON family of PowerPC bootloaders, and in my
45bf8af5f061 libprintf brought in from older PPC/m68k code, but fucking GCC
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
diff changeset
15 MC68x302-based SDSL CPE devices (Hack-o-Rocket and OSDCU).