FreeCalypso > hg > freecalypso-tools
changeset 497:74610c4f10f7
target-utils: added 10 ms delay at the end of abb_power_off()
The deosmification of the ABB access code (replacement of osmo_delay_ms()
bogus delays with correctly-timed ones, which are significantly shorter)
had one annoying side effect: when executing the poweroff command from
any of the programs, one last '=' prompt character was being sent (and
received by the x86 host) as the Calypso board powers off. With delays
being shorter now, the abb_power_off() function was returning and the
standalone program's main loop was printing its prompt before the Iota chip
fully executed the switch-off sequence!
I thought about inserting an endless tight loop at the end of the
abb_power_off() function, but the implemented solution of a 10 ms delay
is a little nicer IMO because if the DEVOFF operation doesn't happen for
some reason in a manual hacking scenario, there won't be an artificial
blocker in the form of a tight loop keeping us from further poking around.
author | Mychaela Falconia <falcon@freecalypso.org> |
---|---|
date | Sat, 25 May 2019 20:44:05 +0000 (2019-05-25) |
parents | 3d73d4d3527f |
children | ca98f800bbf3 |
files | target-utils/libbase/abbdrv.c |
diffstat | 1 files changed, 7 insertions(+), 0 deletions(-) [+] |
line wrap: on
line diff
--- a/target-utils/libbase/abbdrv.c Sat May 25 20:17:27 2019 +0000 +++ b/target-utils/libbase/abbdrv.c Sat May 25 20:44:05 2019 +0000 @@ -102,4 +102,11 @@ abb_init(); serial_flush(); abb_reg_write(VRPCDEV, 0x01); + /* + * TWL3025 datasheet seems to indicate that the time for the DEVOFF + * command to take effect is 5 cycles of the 32.768 kHz clock. + * We'll do an ARM-timed delay of 10 ms before returning from + * this function. + */ + wait_ARM_cycles(13000 * 10); }