FreeCalypso > hg > freecalypso-sw
diff target-utils/libprintf/README @ 11:40f607bb0a2c
target-utils refactored
author | Michael Spacefalcon <msokolov@ivan.Harhan.ORG> |
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date | Wed, 01 May 2013 07:39:35 +0000 |
parents | loadagent/libprintf/README@45bf8af5f061 |
children |
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/target-utils/libprintf/README Wed May 01 07:39:35 2013 +0000 @@ -0,0 +1,15 @@ +The present libprintf is a very light printf implementation that is well-suited +for simple bare-metal programs like loadagent; in the present case it overrides +the much heavier printf implementation in newlib. Programs like the present +loadagent only need printf in order to scribble on the serial console port, +and the most sensible implementation is to have the "character output" function +from the guts of printf point directly to the physical UART output routine, or +a trivial wrapper that turns \n into \r\n. In contrast, newlib's version would +pull in the complete FILE table infrastructure and malloc etc - maybe OK for +more complex embedded programs that use those facilities for other things under +a bona fide RTOS, but it would be disgusting to pull that stuff in for a +minimal program like ours. + +The present printf implementation has been used earlier by the same author +(Michael Spacefalcon) in the StarMON family of PowerPC bootloaders, and in my +MC68x302-based SDSL CPE devices (Hack-o-Rocket and OSDCU).