FreeCalypso > hg > freecalypso-tools

annotate target-utils/libprintf/README @ 995:74024eb17e04

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fc-loadtool help: improve language regarding 16 MiB flash chips In FC project history, 16 MiB flash originally meant Pirelli DP-L10. Then we got FCDEV3B with the same flash (our own design), but now we are discovering more Calypso devices that used such large flash, both late Calypso era (Sony Ericsson K2x0) as well as much earlier ones (FIC FLUID devices.txt file with 2004 dates, Leonardo+ rev 5). Hence we need to migrate to more generic or neutral language in associated documentation, without giving elevated status to specific examples that drove our early project history.
author Mychaela Falconia <falcon@freecalypso.org>
date Sun, 03 Dec 2023 21:11:12 +0000
parents e7502631a0f9
children
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e7502631a0f9 initial import from freecalypso-sw rev 1033:5ab737ac3ad7
Mychaela Falconia <falcon@freecalypso.org>
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1 The present libprintf is a very light printf implementation that is well-suited
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Mychaela Falconia <falcon@freecalypso.org>
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2 for simple bare-metal programs like loadagent; in the present case it overrides
e7502631a0f9 initial import from freecalypso-sw rev 1033:5ab737ac3ad7
Mychaela Falconia <falcon@freecalypso.org>
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3 the much heavier printf implementation in newlib. Programs like the present
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Mychaela Falconia <falcon@freecalypso.org>
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4 loadagent only need printf in order to scribble on the serial console port,
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Mychaela Falconia <falcon@freecalypso.org>
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5 and the most sensible implementation is to have the "character output" function
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Mychaela Falconia <falcon@freecalypso.org>
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6 from the guts of printf point directly to the physical UART output routine, or
e7502631a0f9 initial import from freecalypso-sw rev 1033:5ab737ac3ad7
Mychaela Falconia <falcon@freecalypso.org>
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7 a trivial wrapper that turns \n into \r\n. In contrast, newlib's version would
e7502631a0f9 initial import from freecalypso-sw rev 1033:5ab737ac3ad7
Mychaela Falconia <falcon@freecalypso.org>
parents:
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8 pull in the complete FILE table infrastructure and malloc etc - maybe OK for
e7502631a0f9 initial import from freecalypso-sw rev 1033:5ab737ac3ad7
Mychaela Falconia <falcon@freecalypso.org>
parents:
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9 more complex embedded programs that use those facilities for other things under
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Mychaela Falconia <falcon@freecalypso.org>
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10 a bona fide RTOS, but it would be disgusting to pull that stuff in for a
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Mychaela Falconia <falcon@freecalypso.org>
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11 minimal program like ours.
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Mychaela Falconia <falcon@freecalypso.org>
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13 The present printf implementation has been used earlier by the same author
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Mychaela Falconia <falcon@freecalypso.org>
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14 (Michael Spacefalcon) in the StarMON family of PowerPC bootloaders, and in my
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15 MC68x302-based SDSL CPE devices (Hack-o-Rocket and OSDCU).