Hello everyone,
Like some other users I'm also having trouble accessing GPIO. Let's say I'd like to control these two pins highlighted in red:
(Not sure if I need that jumper, so I added just in case).
Given the breakout-carrier schematic, those pins would be:
And from system_constr.xdc these pins correspond to:
set_property -dict {PACKAGE_PIN AA15 IOSTANDARD LVCMOS25} [get_ports gp_out[63]] ; ## IO_L22P_T3_12
set_property -dict {PACKAGE_PIN AC17 IOSTANDARD LVCMOS25} [get_ports gp_in[63]] ; ## IO_L21P_T3_DQS_12
set_property -dict {PACKAGE_PIN AA14 IOSTANDARD LVCMOS25} [get_ports gp_out[64]] ; ## IO_L22N_T3_12 set_property -dict {PACKAGE_PIN AC16 IOSTANDARD LVCMOS25} [get_ports gp_in[64]] ; ## IO_L21N_T3_DQS_12
If I want to control them from Linux I should add them the gpio-chip offset (906), so 906+63 = 969 and 906+64 = 970:
$ cd /sys/class/gpio;
$ echo 969 > export ; echo 970 > export
$ echo out > gpio969/direction; echo out > gpio970/direction
$ echo 1 > gpio969/value; echo 1 > gpio970/value;
But I've still got 0 V in those pins. What am I missing?
I've also noticed pin names do not match exactly: IO_L22_12_JX2_N != IO_L22N_T3_12... so I may be using the wrong .xdc file. However I've checked dev hdl branch and couldn't find anything better.
Regards,
Leroy.