Manual notation

Binary and hexadecimal

Binary numbers are written with a B at the end. For example, it is expressed as 100B. However, B may be omitted when it is clear that it is a binary number. Hexadecimal numbers are written with an H at the end. For example, it is expressed as 00H and FFH.

unit

1K bytes represent 1024 bytes. The 1M bit is 1024K bits, which is 1,048,576 bits.

MSB, LSB

In the composition of bytes and words, the left represents the high-order bit (MSB, most significant bit) and the right represents the low-order bit (LSB, least significant bit).

Undefined bit

Bits that are not defined in the register are represented by "-". Write 0 to the undefined bits of the register.
Bits that are not defined in the table data defined in VRAM are indicated by diagonal lines. As a general rule, write 0. However, undefined bits are ignored.

Bytes, words, bits

A bit is the smallest unit of data that represents 0 or 1. Eight bits are collectively called a byte. The two bytes are collectively called a word. Words start at an even address.

Boundary

It means defining data from an address that is divisible by a specified number. For example, a 20H byte boundary defines data at addresses starting with 20H, 40H, and so on. The word is a 2-byte boundary.

address

All addresses defined in VDP2 are relative addresses within VDP2. The first address of VDP2 starts with 5E00000H. For example, VRAM is at the relative address 000000H, starting at the absolute address 5E00000H, and the TV screen mode register is at the relative address 180000H, set to the absolute address 5F80000H.