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annotate target-utils/libprintf/README @ 629:e7ba9fcb3637

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target-utils: move loadagent to 0x838000 in preparation for ramImages that load iram.text directly into IRAM
author Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
date Mon, 01 Sep 2014 08:32:22 +0000
parents 40f607bb0a2c
children
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45bf8af5f061 libprintf brought in from older PPC/m68k code, but fucking GCC
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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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:
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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:
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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:
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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:
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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:
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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:
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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:
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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:
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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:
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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:
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11 minimal program like ours.
45bf8af5f061 libprintf brought in from older PPC/m68k code, but fucking GCC
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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12
45bf8af5f061 libprintf brought in from older PPC/m68k code, but fucking GCC
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents:
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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:
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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:
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15 MC68x302-based SDSL CPE devices (Hack-o-Rocket and OSDCU).