NCR RealPOS 70 - Set X Address Register (03 H, XAR); Set Display Control Bits (04 H, DCB); Write Data Byte (05 H, DATA); Write Data Page (06 H, BYTE1, BUTE2

11-8 Chapter 11: APA Customer Display Interface
Set X Address Register (03h, XAR)
ThiscommandsetstheXAR.Bits2through0oftheXARbyteareused,
bits7through3areignored.
Set Display Control Bits (04h, DCB)
Thiscommandsetsthedisplaycontrolbits.Bits5through0oftheDCB
byteareused,bits7and6areignored.
DCB Byte
B7 B6 B5 B4 B3 B2 B1 B0
x x I/D G P1 P0 D H
Write Data Byte (05H, DATA)
ThiscommandwritestheDATAbyte,usingthecurrentdatawrite
mode,intotheDDRAMlocationaddressedbytheXAR,theYAR,the
P1andP0bits,andtheHbit.Thiscommandalsoautomatically
increments(I/D=0)ordecrements(I/D=1)theXandYaddressregisters.
WhentheYARoverflowsfrom
127to0,theXARisalsoincremented,
whentheYARunderflowsfrom0to127,theXARisalsodecremented.
Write Data Page (06h, BYTE1, BUTE2,... BYTE1024)
ThiscommandwritesBYTE1throughBYTE1024,usingthecurrent
datawritemode,intotheDDRAMpageaddressedbytheP1andP0
bits,andtheHbit.ThiscommandignorestheXAR,theYAR,andthe
I/DbitandstoresBYTE1at(XAR,YAR)location(0,0),BYTE2at(0,1),...
BYTE129at(1,0),...
andBYTE1024at(7,127).Thiscommandalsoclears
theXARandtheYAR.