I'm running a transient, then dc analysis:

.param mc_mm_switch=0

.control

save all

tran 500p 2u uic

set appendwrite

write testbench.raw

set appendwrite

dc Vcm 0 1.8 0.01

write testbench.raw

*quit 0

.endc

.end

@Matt Venn can you send the complete .spice file? also try to add a

remzerovec

line before the write instructions.

this is what I have atm: https://github.com/TinyTapeout/tt_asw_1v8/blob/main/xschem/testbench.sch

In some cases if a vector contains no data (for example body current of a mosfet) instead of just skipping it ngspice botches and does not write the raw file. I consider this a ngspice bug. However adding

remzerovec

before

write

fixes the issue (i always add this line before write).

thanks!

@Matt Venn I also saw a problem in your commands. If you have

set appendwrite

before the first

write

command in a testbench you will keep appending data to an ever growing raw file and xschem will load the first sections so you don't see the last simulation data but only the first datasets.

will check

my pattern is like

set f=some_circuit
shell rm -v {$f}*
set appendwrite

...

tran whatever
write {$f}-tran.raw
tran again
write {$f}-tran.raw

dc whatever
write {$f}-dc.raw

so i can freely add and remove analyses without worry