FIES Skew readout mode technical manual

This document gives the technical details of the skew readout mode for FIES. It is meant to include all details in order to reproduce all files and functionality.

For scientific interests, see upcoming article.

To select readout resolution mode, using BIAS, send command @MSETAABBCC where:

Resolution ybin similar unbinned
similar ysize mask
lines readout
time AABBCC

60000 1 27 27 2052 76 81 762701

30000 2 18 36 1026 57 41 571802

20000 3 9 27 684 76 31 760903

15000 4 9 36 513 57 20 570904

10000 6 6 36 342 57 15 570606

6666 9 3 27 228 76 10 760309

5000 12 3 36 171 57 8 570312

3333 18 2 36 114 57 4 570218

What a beginning of a mask file looks like: xover 0 ybin 6 @IMTX3 ampl B @READ01 @MSEE @MSET570606 @MASK1074110910101025111011111111111211... @MASK1173101010091026101110111111121112... @MASK1271110910101025111011111111111211... @MASK1370101010091026101110111111121112... @MASK1469100910101025111011111111111212... . . .

Camera controller

As a first step one needs the latest version of Roy Ostensen's FastPhot camera code. This example has been written for code version v1.5.

cam_info.h:

diff cam_info.h cam_info.h.org 123,125c123,124 < char skew1[8]; /* 298 */ /* some variables for SKEW */ < uint32 cntr[2]; /* 2A0 */ /* iterations counter for SKEW */ < uint32 dummy4[22]; /* 2A8 */ --- > uint16 dummy3[4]; /* 298 */ > uint32 dummy4[24]; /* 2A0 */

config.h:

diff config.h config.h.org 1c1 < #define VERSION "Roy 1.5s" // must be 8 ch string --- > #define VERSION "Roy v1.5" // must be 8 ch string 12d11 < #define SKEW // include code for masked readout

global.h:

diff global.h global.h.org 67,74d66 < #ifdef SKEW < # define MAXORD 99 < # define NLS 76 < extern char mask[NLS*MAXORD]; < extern void maskin(void); < extern void maskout(void); < #endif

readout.c:

diff readout.c readout.c.org 213d212 < else if ( cam.im_tx == 3 ) cam.frame_type = 13; // masked frame,SKEW 220d218 < else if ( cam.im_tx == 3 ) maskout(); // SKEW

rdmask.c:

char mask[7524] = {};

skew.c

FIES BIAS

This is absolutely normal BIAS with exception on just one line in commands.c:
diff commands.c commands.c.org 157c157 < batch_p = fgets(cbuf,210, batch); --- > batch_p = fgets(cbuf,120, batch);

FIES BIAS Scripts

maskin.run

Created with IDL program make_maskin.pro. Used to set camera controller variables and to upload the readout mask into the controller.

skewexp

Used to take 3 bias frames before and after target exposure

skewoff

Used to turn off skew readout mode by resetting camera controller variables to their original values.

hamdord.pro

Currently under testing, might replace the order tracing step done in IRAF.

Last modified: April 19 2023