
AD9920A
Rev. B | Page 26 of 112
Table 12. HBLK Pattern Registers
Register
Length
(Bits)
Range
Description
HBLK_MODE
2
0 to 1 HBLK modes
Enables different HBLK toggle position operations.
0 = normal mode; six toggle positions available for even and odd lines.
If even/odd alternation is not needed, set toggles for even and odd lines to the
same value. In addition to the six toggle positions, the HBLKSTART, HBLKEND,
HBLKLEN, and HBLKREP registers can be used to generate HBLK patterns. If even/
odd alternation is not needed, set toggles for even and odd lines to the same value.
1 = advanced HBLK mode; divides HBLK interval into six repeat areas.
Uses HBLKSTARTA/B/C and RAxHxREPA/B/C registers; the latter, depending on the
mode of operation, are stored in the HBLKTOGO1 to HBLKTOGO6 and HBLKTOGE1
to HBLKTOGE6 registers (Address 0x19 to Address 0x1E; see
Table 63).
2 = test mode only; do not access.
3 = test mode only; do not access.
HBLKSTART
13
0 to 8191 pixel location
Start location for HBLK in HBLK Mode 0 and HBLK Mode 1.
HBLKEND
13
0 to 8191 pixel location
End location for HBLK in HBLK Mode 0 and HBLK Mode 1.
HBLKLEN
13
0 to 8191 pixels
HBLK length in HBLK Mode 0 and HBLK Mode 1.
HBLKREP
13
0 to 8191 repetitions
Number of HBLK repetitions in HBLK Mode 0 and HBLK Mode 1.
HBLKMASK_H1
1
High/low
Masking polarity for H1/H3/H5/H7 during HBLK.
HBLKMASK_H2
1
High/low
Masking polarity for H2/H4/H6/H8 during HBLK.
HBLKMASK_HL
1
High/low
Masking polarity for HL during HBLK.
HBLKMASK_H3P
1
High/low
Masking polarity for H3P during 3-phase mode during HBLK.
HBLKTOGO1
13
0 to 8191 pixel location
First HBLK toggle position for odd lines in HBLK Mode 0.
HBLKTOGO2
13
0 to 8191 pixel location
Second HBLK toggle position for odd lines in HBLK Mode 0.
HBLKTOGO3
13
0 to 8191 pixel location
Third HBLK toggle position for odd lines in HBLK Mode 0.
HBLKTOGO4
13
0 to 8191 pixel location
Fourth HBLK toggle position for odd lines in HBLK Mode 0.
HBLKTOGO5
13
0 to 8191 pixel location
Fifth HBLK toggle position for odd lines in HBLK Mode 0.
HBLKTOGO6
13
0 to 8191 pixel location
Sixth HBLK toggle position for odd lines in HBLK Mode 0.
HBLKTOGE1
13
0 to 8191 pixel location
First HBLK toggle position for even lines in HBLK Mode 0.
HBLKTOGE2
13
0 to 8191 pixel location
Second HBLK toggle position for even lines in HBLK Mode 0.
HBLKTOGE3
13
0 to 8191 pixel location
Third HBLK toggle position for even lines in HBLK Mode 0.
HBLKTOGE4
13
0 to 8191 pixel location
Fourth HBLK toggle position for even lines in HBLK Mode 0.
HBLKTOGE5
13
0 to 8191 pixel location
Fifth HBLK toggle position for even lines in HBLK Mode 0.
HBLKTOGE6
13
0 to 8191 pixel location
Sixth HBLK toggle position for even lines in HBLK Mode 0.
RA0H1REPA/B/C
12
0 to 15 HCLK pulses for
each A, B, and C
HBLK Repeat Area 0. Number of H1 repetitions for HBLKSTARTA/B/C in
HBLK Mode 1 for even lines; odd lines defined using HBLKALT_PAT.
Bits[3:0]: RA0H1REPA. Number of H1 pulses following HBLKSTARTA.
Bits[7:4]: RA0H1REPB. Number of H1 pulses following HBLKSTARTB.
Bits[11:8]: RA0H1REPC. Number of H1 pulses following HBLKSTARTC.