@nataliapc/mcp-openmsx

# CHAPTER 4 - VDP AND DISPLAY SCREEN (Section 6) ## 6. VDP COMMAND USAGE MSX-VIDEO can execute basic graphic operations, which are called VDP commands. These are done by accessing special harware and are available in the GRAPHIC 4 to GRAPHIC 7 modes. These graphic commands have been made easy to implement, requiring only that the necessary parameters be set in the proper registers before invoking them. This section describes these VDP commands.   ## Index - [6. VDP COMMAND USAGE](#6-vdp-command-usage) - [6.1 Coordinate System of VDP Commands](#61-coordinate-system-of-vdp-commands) - [6.2 VDP Commands](#62-vdp-commands) - [6.3 Logical Operations](#63-logical-operations) - [6.4 Area Specification](#64-area-specification) - [6.5 Use of Each Command](#65-use-of-each-command) - [6.5.1 HMMC (CPU -> VRAM high-speed transfer)](#651-hmmc-cpu---vram-high-speed-transfer) - [6.5.2 YMMM (high-speed transfer between VRAM in Y direction)](#652-ymmm-high-speed-transfer-between-vram-in-y-direction) - [6.5.3 HMMM (high-speed transfer between VRAM)](#653--hmmm-high-speed-transfer-between-vram) - [6.5.4 HMMV (painting the rectangle in high speed)](#654-hmmv-painting-the-rectangle-in-high-speed) - [6.5.5 LMMC (CPU -> VRAM logical transfer)](#655-lmmc-cpu---vram-logical-transfer) - [6.5.6 LMCM (VRAM - CPU logical transfer)](#656-lmcm-vram---cpu-logical-transfer) - [6.5.7. LMMM (VRAM->VRAM logical transfer)](#657-lmmm-vram-vram-logical-transfer) - [6.5.8 LMMV (VRAM logical paint)](#658-lmmv-vram-logical-paint) - [6.5.9 LINE (drawing a line)](#659-line-drawing-a-line) - [6.5.10 SRCH (colour code search)](#6510-srch-colour-code-search) - [6.5.11 PSET (drawing a point)](#6511-pset-drawing-a-point) - [6.5.12 POINT (reading a colour code)](#6512-point-reading-a-colour-code) - [6.6 Speeding Up Commands](#66-speeding-up-commands) - [6.7 Register Status at Command Termination](#67-register-status-at-command-termination) - [Changes from the original](#changes-from-the-original)   ### 6.1 Coordinate System of VDP Commands When VDP commands are executed, the location of the source and destination points are represented as (X, Y) coordinates as shown in [Figure 4.72](#figure-472--coordinate-system-of-vram). When commands are executed, there is no page division and the entire 128K bytes VRAM is placed in a large coordinate system. ##### _Figure 4.72 Coordinate system of VRAM_ ``` GRAPHIC 4 (SCREEN 5) GRAPHIC 5 (SCREEN 6) ------------------------------ 00000H ------------------------------ | (0,0) (255,0) | | | (0,0) (511,0) | | Page 0 | | | Page 0 | | (0,255) (255,255) | | | (0,255) (511,255) | |----------------------------| 08000H |----------------------------| | (0,256) (255,256) | | | (0,256) (511,256) | | Page 1 | | | Page 1 | | (0,511) (255,511) | | | (0,511) (511,511) | |----------------------------| 10000H |----------------------------| | (0,512) (255,512) | | | (0,512) (511,512) | | Page 2 | | | Page 2 | | (0,767) (255,767) | | | (0,767) (511,767) | |----------------------------| 18000H |----------------------------| | (0,768) (255,768) | | | (0,768) (511,768) | | Page 3 | | | Page 3 | | (0,1023) (255,1023) | | | (0,1023) (511,1023) | ------------------------------ 1FFFFH ------------------------------ GRAPHIC 7 (SCREEN 8) GRAPHIC 6 (SCREEN 7) ------------------------------ 00000H ------------------------------ | (0,0) (255,0) | | | (0,0) (511,0) | | Page 0 | | | Page 0 | | (0,255) (255,255) | | | (0,255) (511,255) | |----------------------------| 10000H |----------------------------| | (0,256) (255,256) | | | (0,256) (511,256) | | Page 1 | | | Page 1 | | (0,511) (255,511) | | | (0,511) (511,511) | ------------------------------ 1FFFFH ------------------------------ ```   ### 6.2 VDP Commands There are 12 types of VDP commands which can be executed by MSX-VIDEO. These are shown in [Table 4.5](#table-45--list-of-vdp-commands). ##### _Table 4.5 List of VDP commands_ ``` ---------------------------------------------------------------------------- | Command name | Destination | Source | Units | Mnemonic | R#46 (4 hi ord) | |--------------+-------------+--------+-------+----------+-----------------| | | VRAM | CPU | bytes | HMMC | 1 1 1 1 | | High speed | VRAM | VRAM | bytes | YMMM | 1 1 1 0 | | move | VRAM | VRAM | bytes | HMMM | 1 1 0 1 | | | VRAM | VDP | bytes | HMMV | 1 1 0 0 | |--------------+-------------+--------+-------+----------+-----------------| | | VRAM | CPU | dots | LMMC | 1 0 1 1 | | Logical | CPU | VRAM | dots | LMCM | 1 0 1 0 | | move | VRAM | VRAM | dots | LMMM | 1 0 0 1 | | | VRAM | VDP | dots | LMMV | 1 0 0 0 | |--------------+-------------+--------+-------+----------+-----------------| | Line | VRAM | VDP | dots | LINE | 0 1 1 1 | |--------------+-------------+--------+-------+----------+-----------------| | Search | VRAM | VDP | dots | SRCH | 0 1 1 0 | |--------------+-------------+--------+-------+----------+-----------------| | Pset | VRAM | VDP | dots | PSET | 0 1 0 1 | |--------------+-------------+--------+-------+----------+-----------------| | Point | VDP | VRAM | dots | POINT | 0 1 0 0 | |--------------+-------------+--------+-------+----------+-----------------| | | ---- | ---- | ----- | ---- | 0 0 1 1 | | Reserved | ---- | ---- | ----- | ---- | 0 0 1 0 | | | ---- | ---- | ----- | ---- | 0 0 0 1 | |--------------+-------------+--------+-------+----------+-----------------| | Stop | ---- | ---- | ----- | ---- | 0 0 0 0 | ---------------------------------------------------------------------------- ``` * When data is written in R#46 (Command register), MSX-VIDEO begins to execute the command after setting 1 to bit 0 (CE/Command Execute) of the status register S#2. Necessary parameters should be set in register R#32 to R#45 before the command is executed. * When the execution of the command ends, CE becomes 0. * To stop the execution of the command, execute STOP command. * Actions of the commands are guaranteed only in the bitmap modes (GRAPHIC 4 to GRAPHIC 7).   ### 6.3 Logical Operations When commands are executed, various logical operations can be done between data in VRAM and the specified data. Each operation will be done according to the rules listed in [Table 4.6](#table-46--list-of-logical-operations). In the table, SC represents the source color and DC represents the destination colour. IMP, AND, OR, EOR and NOT write the result of each operation to the destination. In operations whose names are preceded by "T", dots which correspond with SC=0 are not the objects of the operations and remains as DC. Using these operations enables only colour portions of two figures to be overlapped, so they are especially effective for animations. [List 4.7](#list-47--example-of-the-logical-operation-with-t) shows an example of these operations. ##### _Table 4.6 List of logical operations_ ``` ------------------------------------------------------------------------- | Logical name | |L03 L02 L01 L00| |--------------+----------------------------------------+---------------| | | | | | IMP | DC=SC | 0 0 0 0 | | | | | | AND | DC=SCxDC | 0 0 0 1 | | | | | | OR | DC=SC+DC | 0 0 1 0 | | | __ __ | | | EOR | DC=SCxDC+SCxDC | 0 0 1 1 | | | __ | | | NOT | DC=SC | 0 1 0 0 | | | | | | ---- | | 0 1 0 1 | | | | | | ---- | | 0 1 1 0 | | | | | | ---- | | 0 1 1 1 | | | | | |--------------+----------------------------------------+---------------| | | | | | TIMP | if SC=0 then DC=DC else DC=SC | 1 0 0 0 | | | | | | TAND | if SC=0 then DC=DC else DC=SCxDC | 1 0 0 1 | | | | | | TOR | if SC=0 then DC=DC else DC=SC+DC | 1 0 1 0 | | | __ __ | | | TEOR | if SC=0 then DC=DC else DC=SCxDC+SCxDC | 1 0 1 1 | | | __ | | | TNOT | if SC=0 then DC=DC else DC=SC | 1 1 0 0 | | | | | | ---- | | 1 1 0 1 | | | | | | ---- | | 1 1 1 0 | | | | | | ---- | | 1 1 1 1 | | | | | ------------------------------------------------------------------------- ``` * SC = Source colour code * DC = Destination colour code * EOR = Exclusive OR ##### _List 4.7 Example of the logical operation with T_ ``` 1000 '*********************************************************** 1010 ' List 4.7 logical operation with T 1020 '*********************************************************** 1030 ' 1040 SCREEN8 : COLOR 15,0,0 : CLS 1050 DIM A%(3587) 1060 ' 1070 LINE (50,50)-(60,100),48,B : PAINT (51,51),156,48 1080 CIRCLE (55,30),30,255 : PAINT (55,30),240,255 1090 COPY(20,0)-(90,100) TO A% 1100 CLS 1110 ' 1120 R=RND(-TIME) 1130 FOR Y=0 TO 100 STEP 3 1140 X=INT(RND(1)*186) 1150 COPY A% TO (X,Y),,TPSET 1160 NEXT 1170 ' 1180 GOTO 1180 ```   ### 6.4 Area Specification AREA-MOVE commands are for transferring screen data inside areas surrounded by a rectangle. The area to be transferred is specified by one vertex and the length of each side of the rectangle as shown in [Figure 4.73](#figure-473--area-specification). SX and SY represent the basic point of the rectangle to be transferred and NX and NY represent the lengt of each side in dots. The two bits, DIX and DIY, are for the direction of transferring data (the meaning of DIX and DIY depends on the type of command). The point where the area is to be transferred is specified in DX and DY. ##### _Figure 4.73 Area specification_ ``` ---------------------------------------------------------------- | | | (SX,SY) | | x----------------- --> | | | | DIX | | | | | | | | | | | | | | ------------------ --+ | | | DIY | | | V | | | | (DX,DY) | | +-> x----------------- | | | | | | | | | | | | | | | | | | ------------------ | | | ---------------------------------------------------------------- ```   ### 6.5 Use of Each Command Commands are clasified into three types, high-speed transfer commands, logical transfer commands, and drawing commands. This section describes the commands and their use.   #### 6.5.1 HMMC (CPU -> VRAM high-speed transfer) Data is transferred into the specified area of VRAM from the CPU (see [Figure 4.74](#figure-474--action-of-hmmc-command)). Logical operations cannot be specified. Data is transferred in bytes in high-speed transfer commands such as HMMC. Note that the low order bit of the X-coordinate is not referred to in GRAPHIC 4, or 6 modes. The two low order bits are not referred to in GRAPHIC 5 mode (see [Figure 4.75](#figure-475--dots-not-to-be-referred-to)). Set the parameters as shown in [Figure 4.76](#figure-476--register-settings-of-hmmc-command) to the appropriate registers. At this point, write only the first byte of data to be transferred from the CPU in R#44. Writing the command code F0H in R#46 causes the command to be executed, and UMSX-VIDEO receives data from R#44 and writes it to VRAM, then waits for data from the CPU. The CPU writes data after the second byte in R#44. Note that data should be transferred after MSX-VIDEO can receive data (in the case that TR bit is "1"), referring to TR bit of S#2. When the CE bit of S#2 is "0", this means that all data has been transferred (see figure 4.77). [List 4.8](#list-48--example-of-hmmc-command-execution) shows an example of using HMMC. ##### _Figure 4.74 Action of HMMC command_ ``` VRAM or expansion RAM --------------------------------------------------- | | MSX-VIDEO CPU | | ------- ------- | (DX,DY) | | | | | | x------------------------ --> DIX | | | | | | | NX | | | | | | | | NY |<----------------+----| |-----| | | | | | | | | | | ------------------------- | | | | | | | DIY | | | | | | V | | | | | | | ------- ------- | | --------------------------------------------------- MXD: select the destination memory 0 = VRAM, 1 = expansion RAM NX: number of dots to be transferred in X direction (0 to 511)* NY: number of dots to be transferred in Y direction (0 to 1023) DIX: direction of NX from the origin 0 = right, 1 = left DIY: direction of NY from the origin 0 = below, 1 = above DX: destination origin X-coordinate (0 to 511)* DY: destination origin Y-coordinate (0 to 1023) CLR (R#44:Colour register): 1st byte of data to be transferred * The one low-order bit for GRAPHIC 4 and 6 modes, or two low-order bits for GRAPHIC 5 mode of the DX and NX registers are ignored. ``` ##### _Figure 4.75 Dots not to be referred to_ ``` MSB 7 6 5 4 3 2 1 0 LSB ----------------------------------------- GRAPHIC 4 | : : : | : : : | ----------------------------------------- (1) (2) Since 1 VRAM byte represents 2 dots, 1 low order bit of X-coordinate is not referred to. MSB 7 6 5 4 3 2 1 0 LSB ----------------------------------------- GRAPHIC 5 | : | : | : | : | ----------------------------------------- (1) (2) (3) (4) Since 1 VRAM byte represents 4 dots, 2 low order bits of X-coordinate are not referred to. MSB 7 6 5 4 3 2 1 0 LSB ----------------------------------------- GRAPHIC 6 | : : : | : : : | ----------------------------------------- (1) (2) Since 1 VRAM byte represents 2 dots, 1 low order bit of X-coordinate is not referred to. ``` ##### _Figure 4.76 Register settings of HMMC command_ ``` > HMMC register setup MSB 7 6 5 4 3 2 1 0 LSB ----------------------------------------- R#36 | DX7| DX6| DX5| DX4| DX3| DX2| DX1| DX0| ----------------------------------------- DX ---+ R#37 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | DX8| | ----------------------------------------- | | destination origin ----------------------------------------- | R#38 | DY7| DY6| DY5| DY4| DY3| DY2| DY1| DY0| | ----------------------------------------- DY ---+ R#39 | 0 | 0 | 0 | 0 | 0 | 0 | DY9| DY8| ----------------------------------------- ----------------------------------------- R#40 | NX7| NX6| NX5| NX4| NX3| NX2| NX1| NX0| ----------------------------------------- NX ⟶ Number of dots in X direction to be transferred R#41 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | NX8| ----------------------------------------- ----------------------------------------- R#42 | NY7| NY6| NY5| NY4| NY3| NY2| NY1| NY0| ----------------------------------------- NY ⟶ Number of dots in Y direction to be transferred R#43 | 0 | 0 | 0 | 0 | 0 | 0 | NY9| NY8| ----------------------------------------- ----------------------------------------- --+ R#44 | CR7| CR6| CR5| CR4| CR3| CR2| CR1| CR0| CLR (GRAPHIC 4,6) | ----------------------------------------- | | | | | +-------------------+-------------------+ | X=2N X=2N+1 (N=0, 1, ..., 127) | | ----------------------------------------- | | CR7| CR6| CR5| CR4| CR3| CR2| CR1| CR0| CLR (GRAPHIC 5) | data to be transferred ----------------------------------------- | | | | | | | +---------+---------+---------+---------+ | X=4N X=4N+1 X=4N+2 X=4N+3 (N=0, 1, ..., 127) | | ----------------------------------------- | | CR7| CR6| CR5| CR4| CR3| CR2| CR1| CR0| CLR (GRAPHIC 7) | ----------------------------------------- --+ 1 byte per dot ----------------------------------------- R#45 | 0 | -- | MXD| -- | DIY| DIX| -- | -- | ARG (Argument register) ----------------------------------------- | | direction (X) | | | +-> direction (Y) | +-----------> select destination memory > HMMC command execution MSB 7 6 5 4 3 2 1 0 LSB ----------------------------------------- R#46 | 1 | 1 | 1 | 1 | -- | -- | -- | -- | CMR ----------------------------------------- ``` ##### _Figure 4.77 HMMC command execution flow chart_ ``` /-------------------\ | HMMC start | \-------------------/ | --------------------- | register setup | --------------------- | --------------------- | command execution | --------------------- | +---------------->| | | | --------------------------- | | Read status register #2 | | --------------------------- | | | //////////+\\\\\\\\\\ Yes (CE bit = 0) | | command end? |-------------------+ | \\\\\\\\\\+////////// | | | No (CE bit = 1) | | //////////+\\\\\\\\\\ | |<------| transfer? | | | No \\\\\\\\\\+////////// | | (TR bit=0) | Yes (TR bit = 1) | | --------------------- | | | transfer data | | | --------------------- | | | | +-----------------+ | | +-----------------------------+ | V /--------------------\ | HMMC end | \--------------------/ ``` ##### _List 4.8 Example of HMMC command execution_ ``` ;**************************************************************** ; List 4.8 HMMC sample ; to use, set H, L, D, E, IX and go ; RAM (IX) ⟶ VRAM (H,L)-(D,E) ;**************************************************************** ; RDVDP: EQU 0006H WRVDP: EQU 0007H ;----- program start ----- HMMC: DI ;disable interrupt CALL WAIT.VDP ;wait end of command LD A,(WRVDP) LD C,A INC C ;C := PORT#1's address LD A,36 OUT (C),A LD A,17+80H OUT (C),A ;R#17 := 36 INC C INC C ;C := PORT#3's address XOR A OUT (C),H ;DX OUT (C),A OUT (C),L ;DY OUT (C),A LD A,H ;make NX and DIX SUB A LD D,00000100B JR NC,HMMC1 LD D,00000000B NEG HMMC1: LD H,A ;H := NX , D := DIX LD A,L SUB A LD E,00001000B JR NC,HMMC2 LD E,00000000B NEG HMMC2: LD L,A ;L := NY , E := DIY XOR A OUT (C),H ;NX OUT (C),A OUT (C),L ;NY OUT (C),A LD H,(IX+0) OUT (C),H ;first DATA LD A,D OR E OUT (C),A ;DIX and DIY LD A,0F0H OUT (C),A ;HMMC command LD A,(WRVDP) LD C,A ;C := PORT#1's address INC C LD A,44+80H OUT (C),A LD A,17+80H OUT (C),A INC C INC C LOOP: LD A,2 CALL GET.STATUS BIT 0,A ;check CE bit JR Z,EXIT BIT 7,A ;check TR bit JR Z,LOOP INC IX LD A,(IX+0) OUT (C),A JR LOOP EXIT: LD A,0 CALL GET.STATUS ;when exit, you must select S#0 EI RET GET.STATUS: ;read status register specified by A PUSH BC LD BC,(WRVDP) INC C OUT (C),A LD A,8FH OUT (C),A LD BC,(RDVDP) INC C IN A,(C) POP BC RET WAIT.VDP: ;wait VDP ready LD A,2 CALL GET.STATUS AND 1 JR NZ,WAIT.VDP XOR A CALL GET.STATUS RET END ```   #### 6.5.2 YMMM (high-speed transfer between VRAM in Y direction) Data from a specified VRAM area is transferred into another area in VRAM. Note that transfers using this command can only be done in the Y direction (see [Figure 4.78](#figure-478--actions-of-ymmm-command)). After setting the data as shown in [Figure 4.79](#figure-479--register-settings-of-ymmm-command) in the proper registers, writing command code E0H in R#46 causes the command to be executed. When the CE bit of S#2 is "1", it indicates that the command is currently being executed. [List 4.9](#list-49--example-of-ymmm-command-execution) shows an example of using YMMM. ##### _Figure 4.78 Actions of YMMM command_ ``` VRAM or expansion RAM --------------------------------------------------- | | | (DX,DY) | | x------------------------| | | | | | | | | | | -------------------------| | ^ | | | | | | | | (DX,SY) | | x------------------------| ⟶ DIX | | | | | NY | | | | | -------------------------| | | DIY | | V | --------------------------------------------------- MXD: select the destination memory 0 = VRAM, 1 = expansion RAM SY: source origin Y-coordinate (0 to 1023) NY: number of dots to be transferred in Y direction (0 to 1023) DIX: set which to be transferred, to te right end or to the left end of the screen from the source origin 0 = right, 1 = left DIY: direction of NY from the origin 0 = below, 1 = above DX: destination origin X-coordinate (0 to 511)* DY: destination origin Y-coordinate (0 to 1023) * The one low-order bit for GRAPHIC 4 and 6 modes, or two low-order bits for GRAPHIC 5 mode of the DX register are ignored. ``` ##### _Figure 4.79 Register settings of YMMM command_ ``` > YMMM register setup MSB 7 6 5 4 3 2 1 0 LSB ----------------------------------------- R#34 | SY7| SY6| SY5| SY4| SY3| SY2| SY1| SY0| ----------------------------------------- SY ⟶ source origin R#35 | 0 | 0 | 0 | 0 | 0 | 0 | SY9| SY8| ----------------------------------------- ----------------------------------------- R#36 | DX7| DX6| DX5| DX4| DX3| DX2| DX1| DX0| ----------------------------------------- DX ⟶ destination and source origin R#37 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | DX8| ----------------------------------------- ----------------------------------------- R#38 | DY7| DY6| DY5| DY4| DY3| DY2| DY1| DY0| ----------------------------------------- DY ⟶ destination origin R#39 | 0 | 0 | 0 | 0 | 0 | 0 | DY9| DY8| ----------------------------------------- ----------------------------------------- R#42 | NY7| NY6| NY5| NY4| NY3| NY2| NY1| NY0| ----------------------------------------- NY ⟶ number of dots to be transferred in Y direction R#43 | 0 | 0 | 0 | 0 | 0 | 0 | NY9| NY8| ----------------------------------------- ----------------------------------------- R#45 | 0 | -- | MXD| -- | DIY| DIX| -- | -- | ARG (Argument register) ----------------------------------------- | | direction (X) | | | +-> direction (Y) | +-----------> select destination memory > YMMM command execution MSB 7 6 5 4 3 2 1 0 LSB ----------------------------------------- R#46 | 1 | 1 | 1 | 0 | -- | -- | -- | -- | CMR ----------------------------------------- ``` ##### _List 4.9 Example of YMMM command execution_ ``` ;**************************************************************** ; List 4.9 YMMM sample ; to use, set L, E, B, C, D(bit 2) and go ; VRAM (B,L)-(*,E) ⟶ VRAM (B,C) ; DIX must be set in D(bit 2) ;**************************************************************** ; RDVDP: EQU 0006H WRVDP: EQU 0007H ;----- program start ----- YMMM: DI ;disable interrupt PUSH BC ;save destination CALL WAIT.VDP ;wait end of command LD A,(WRVDP) LD C,A INC C ;C := PORT#1's address LD A,34 OUT (C),A LD A,17+80H OUT (C),A ;R#17 := 34 INC C INC C ;C := PORT#3's address XOR A OUT (C),L ;SY OUT (C),A LD A,L ;make NY and DIY SUB A LD E,00001000B JP NC,YMMM1 LD E,00000000B NEG YMMM1: LD L,A ;L := NY , D := DIY LD A,D OR E POP DE ;restore DX,DY PUSH AF ;save DIX,DIY XOR A OUT (C),D ;DX OUT (C),A OUT (C),E ;DY OUT (C),A OUT (C),A ;dummy OUT (C),A ;dummy OUT (C),L ;NY OUT (C),A OUT (C),A ;dummy POP AF OUT (C),A ;DIX and DIY LD A,11100000B ;YMMM command OUT (C),A EI RET GET.STATUS: PUSH BC LD BC,(WRVDP) INC C OUT (C),A LD A,8FH OUT (C),A LD BC,(RDVDP) INC C IN A,(C) POP BC RET WAIT.VDP: LD A,2 CALL GET.STATUS AND 1 JP NZ,WAIT.VDP XOR A CALL GET.STATUS RET END ```   #### 6.5.3 HMMM (high-speed transfer between VRAM) Data of specified VRAM area is transferred into another area in VRAM (see [Figure 4.80](#figure-480--actions-of-hmmm-command)). After setting the parameters as shown in [Figure 4.81](#figure-481--register-settings-of-hmmm-command), writing D0H in R#46 causes the command to be executed. While the command is being executed, CE bit of S#2 is "1". [List 4.10](#list-410--example-of-hmmm-command-execution) shows an example of using HMMM. ##### _Figure 4.80 Actions of HMMM command_ ``` VRAM or expansion RAM ---------------------------------------------------------------- | | | (SX,SY) | | ------------------ --> | | | NX | DIX | | | | | | | NY | | | | | | | ------------------ --+ | | | DIY | | | V | | | | (DX,DY) | | +-> ------------------ | | | | | | | | | | | | | | | | | | ------------------ | | | ---------------------------------------------------------------- MXS: select the source memory 0 = VRAM, 1 = expansion RAM MXD: select the destination memory 0 = VRAM, 1 = expansion RAM SX: source origin X-coordinate (0 to 511)* SY: source origin Y-coordinate (0 to 1023) NX: number of dots to be transferred in X direction (0 to 511)* NY: number of dots to be transferred in Y direction (0 to 1023) DIX: direction of NX from the origin 0 = right, 1 = left DIY: direction of NY from the origin 0 = below, 1 = above DX: destination origin X-coordinate (0 to 511)* DY: destination origin Y-coordinate (0 to 1023) * The one low-order bit for GRAPHIC 4 and 6 modes, or two low-order bits for GRAPHIC 5 mode of the SX, DX, and NX register are ignored. ``` ##### _Figure 4.81 Register settings of HMMM command_ ``` > HMMM register setup MSB 7 6 5 4 3 2 1 0 LSB ----------------------------------------- R#32 | SX7| SX6| SX5| SX4| SX3| SX2| SX1| SX0| |----+----+----+----+----+----+----+----| SX ---+ R#33 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | SX8| | ----------------------------------------- | | source origin ----------------------------------------- | R#34 | SY7| SY6| SY5| SY4| SY3| SY2| SY1| SY0| | |----+----+----+----+----+----+----+----| SY ---+ R#35 | 0 | 0 | 0 | 0 | 0 | 0 | SY9| SY8| ----------------------------------------- ----------------------------------------- R#36 | DX7| DX6| DX5| DX4| DX3| DX2| DX1| DX0| |----+----+----+----+----+----+----+----| DX ---+ R#37 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | DX8| | ----------------------------------------- | | destination origin ----------------------------------------- | R#38 | DY7| DY6| DY5| DY4| DY3| DY2| DY1| DY0| | |----+----+----+----+----+----+----+----| DY ---+ R#39 | 0 | 0 | 0 | 0 | 0 | 0 | DY9| DY8| ----------------------------------------- ----------------------------------------- R#40 | NX7| NX6| NX5| NX4| NX3| NX2| NX1| NX0| |----+----+----+----+----+----+----+----| NX ⟶ Number of dots in X direction to be transferred R#41 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | NX8| ----------------------------------------- ----------------------------------------- R#42 | NY7| NY6| NY5| NY4| NY3| NY2| NY1| NY0| |----+----+----+----+----+----+----+----| NY ⟶ Number of dots in Y direction to be transferred R#43 | 0 | 0 | 0 | 0 | 0 | 0 | NY9| NY8| ----------------------------------------- ----------------------------------------- R#45 | 0 | -- | MXD| MXS| DIY| DIX| -- | -- | ARG (Argument register) ----------------------------------------- | | | direction (X) | | | | | +-> direction (Y) | | | +------> select source memory | +-----------> select destination memory > HMMM command execution MSB 7 6 5 4 3 2 1 0 LSB ----------------------------------------- R#46 | 1 | 1 | 0 | 1 | -- | -- | -- | -- | CMR ----------------------------------------- ``` ##### _List 4.10 Example of HMMM command execution_ ``` ;**************************************************************** ; List 4.10 HMMM sample ; to use, set H, L, D, E, B, C and go ; VRAM (H,L)-(D,E) ⟶ VRAM (B,C) ; DIX must be set in D(bit 2) ;**************************************************************** ; RDVDP: EQU 0006H WRVDP: EQU 0007H ;----- program start ----- HMMM: DI ;disable interrupt PUSH BC ;save destination CALL WAIT.VDP ;wait end of command LD A,(WRVDP) LD C,A INC C ;C := PORT#1's address LD A,32 OUT (C),A LD A,80H+17 OUT (C),A ;R#17 := 32 INC C INC C ;C := PORT#3's address XOR A OUT (C),H ;SX OUT (C),A OUT (C),L ;SY OUT (C),A LD A,H ;make NX and DIX SUB A LD D,00000100B JP NC,HMMM1 LD D,00000000B NEG HMMM1: LD H,A ;H := NX , D := DIX LD A,L ;make NY and DIY SUB A LD E,00001000B JP NC,HMMM2 LD E,00000000B NEG HMMM2: LD L,A ;L := NY , E := DIY LD A,D OR E POP DE ;restore DX,DY PUSH AF ;save DIX,DIY XOR A OUT (C),D ;DX OUT (C),A OUT (C),E ;DY OUT (C),A OUT (C),H ;NX OUT (C),A OUT (C),L ;NY OUT (C),A OUT (C),A ;dummy POP AF OUT (C),A ;DIX and DIY LD A,11010000B ;HMMM command OUT (C),A EI RET GET.STATUS: PUSH BC LD BC,(WRVDP) INC C OUT (C),A LD A,8FH OUT (C),A LD BC,(RDVDP) INC C IN A,(C) POP BC RET WAIT.VDP: LD A,2 CALL GET.STATUS AND 1 JP NZ,WAIT.VDP XOR A CALL GET.STATUS RET END ```   #### 6.5.4 HMMV (painting the rectangle in high speed) Each byte of data in the specified VRAM area is painted by the specified colour code (see [Figure 4.82](#figure-482--actions-of-hmmc-command)) After setting the parameters as shown in [Figure 4.83](#figure-483--register-settings-of-hmmv-command), writing C0H in R#46 causes the command to be executed. While the command is being executed, the CE bit of S#2 is 1. [List 4.11](#list-411--example-of-hmmv-command-execution) shows an example of using HMMV. ##### _Figure 4.82 Actions of HMMC command_ ``` VRAM or expansion RAM --------------------------------------------------- | | MSX-VIDEO | | ------- | (DX,DY) | | | | x------------------------ --> DIX | | | | | NX | | | | | | NY |<----------------+----| | | | | | | | | ------------------------- | | | | | DIY | | | | V | | | | | ------- | | --------------------------------------------------- MXD: select memory 0 = VRAM, 1 = expansion RAM NX: number of dots to be painted in X direction (0 to 511)* NY: number of dots to be painted in Y direction (0 to 1023) DIX: direction of NX from the origin 0 = right, 1 = left DIY: direction of NY from the origin 0 = below, 1 = above DX: origin X-coordinate (0 to 511)* DY: origin Y-coordinate (0 to 1023) CLR (R#44:Colour register): Painted data * The one low-order bit for GRAPHIC 4 and 6 modes, or two low-order bits for GRAPHIC 5 mode of the DX and NX registers are ignored. ``` ##### _Figure 4.83 Register settings of HMMV command_ ``` > HMMV register setup MSB 7 6 5 4 3 2 1 0 LSB ----------------------------------------- R#36 | DX7| DX6| DX5| DX4| DX3| DX2| DX1| DX0| |----+----+----+----+----+----+----+----| DX ---+ R#37 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | DX8| | ----------------------------------------- | | origin ----------------------------------------- | R#38 | DY7| DY6| DY5| DY4| DY3| DY2| DY1| DY0| | |----+----+----+----+----+----+----+----| DY ---+ R#39 | 0 | 0 | 0 | 0 | 0 | 0 | DY9| DY8| ----------------------------------------- ----------------------------------------- R#40 | NX7| NX6| NX5| NX4| NX3| NX2| NX1| NX0| |----+----+----+----+----+----+----+----| NX ⟶ number of dots in X direction to be painted R#41 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | NX8| ----------------------------------------- ----------------------------------------- R#42 | NY7| NY6| NY5| NY4| NY3| NY2| NY1| NY0| |----+----+----+----+----+----+----+----| NY ⟶ number of dots inY direction to be painted R#43 | 0 | 0 | 0 | 0 | 0 | 0 | NY9| NY8| ----------------------------------------- ----------------------------------------- --+ R#44 | CR7| CR6| CR5| CR4| CR3| CR2| CR1| CR0| CLR (GRAPHIC 4,6) | ----------------------------------------- | | | | | +-------------------+-------------------+ | X=2N X=2N+1 (N=0, 1, ..., 127) | | ----------------------------------------- | | CR7| CR6| CR5| CR4| CR3| CR2| CR1| CR0| CLR (GRAPHIC 5) | data to be painted ----------------------------------------- | | | | | | | +---------+---------+---------+---------+ | X=4N X=4N+1 X=4N+2 X=4N+3 (N=0, 1, ..., 127) | | ----------------------------------------- | | CR7| CR6| CR5| CR4| CR3| CR2| CR1| CR0| CLR (GRAPHIC 7) | ----------------------------------------- --+ 1 byte / dot ----------------------------------------- R#45 | 0 | -- | MXD| -- | DIY| DIX| -- | -- | ARG (Argument register) ----------------------------------------- | | painting direction (X) | | | +-> painting direction (Y) | +-----------> memory selection > HMMV command execution MSB 7 6 5 4 3 2 1 0 LSB ----------------------------------------- R#46 | 1 | 1 | 0 | 0 | -- | -- | -- | -- | CMR ----------------------------------------- ``` ##### _List 4.11 Example of HMMV command execution_ ``` ;**************************************************************** ; List 4.11 HMMV sample ; to use, set H, L, D, E, B and go ; B ⟶ VRAM (H,L)-(D,E) fill ;**************************************************************** ; RDVDP: EQU 0006H WRVDP: EQU 0007H ;----- program start ----- HMMV: DI ;disable interrupt CALL WAIT.VDP ;wait end of command LD A,(WRVDP) LD C,A INC C ;C := PORT#1's address LD A,36 OUT (C),A LD A,80H+17 OUT (C),A ;R#17 := 36 INC C INC C ;C := PORT#3's address XOR A OUT (C),H ;DX OUT (C),A OUT (C),L ;DY OUT (C),A LD A,H ;make NX and DIX SUB A LD D,00000100B JP NC,HMMV1 LD D,00000000B NEG HMMV1: LD H,A ;H := NX LD A,L ;make NY and DIY SUB A LD E,00001000B JP NC,HMMV2 LD E,00000000B NEG HMMV2: OUT (C),H LD H,A ;H := NY XOR A OUT (C),A OUT (C),H OUT (C),A OUT (C),B ;fill data XOR A OR D OR E OUT (C),A ;DIX and DIY LD A,11000000B ;HMMV command OUT (C),A EI RET GET.STATUS: PUSH BC LD BC,(WRVDP) INC C OUT (C),A LD A,8FH OUT (C),A LD BC,(RDVDP) INC C IN A,(C) POP BC RET WAIT.VDP: LD A,2 CALL GET.STATUS AND 1 JP NZ,WAIT.VDP XOR A CALL GET.STATUS RET END ```   #### 6.5.5 LMMC (CPU -> VRAM logical transfer) Data is transferred from the CPU to thespecified VRAM area in dots (see [Figure 4.84](#figure-484--action-of-lmmc-command)). Logical operations with the source can be specified. In the logical transfer commands, such as LMMC, data is transfered in dots and one byte is required for the information of one pixel in all screen modes. After setting the data as shown in [Figure 4.85](#figure-485--register-settings-of-lmmc-command), write command code B0H in R#46. At this point, logical operations can be specified by using the 4 low order bits of the command register. Data is transferred with reference to the TR and CE bit of S#2, as in HMMC (see [Figure 4.86](#figure-486--lmmc-command-execution-flow-chart)). [List 4.12](#list-412--example-of-lmmc-command-execution) shows an example of using LMMC. ##### _Figure 4.84 Action of LMMC command_ ``` VRAM or expansion RAM -----------------------------------