Using LEDs, LCDs and GLCDs in Microcontroller Projects

6.3 DDRAM Addresses

The DDRAM addresses of various display sizes are given in this section. Table 6.2 gives the 1-row display DDRAM addresses.

Table 6.2 1-row display DDRAM addresses.

Display Size	Character Position	DDRAM Address
1 × 8	00 to 07	0 × 00 to 0 × 07
1 × 16	00 to 15	0 × 00 to 0 × 0F
1 × 20	00 to 19	0 × 00 to 0 × 13
1 × 24	00 to 23	0 × 00 to 0 × 17
1 × 32	00 to 31	0 × 00 to 0 × 1F
1 × 40	00 to 39	0 × 00 to 0 × 27

The 2-row display DDRAM addresses are given in Table 6.3. Notice that the second row starts from address 0 × 40.

Table 6.3 2-row display DDRAM addresses.

Display Size	Character Position	DDRAM Address
2 × 16	00 to 15	0 × 00 to 0 × 0F and 0 × 40 to 0 × 4F
2 × 20	00 to 19	0 × 00 to 0 × 13 and 0 × 40 to 0 × 53
2 × 24	00 to 23	0 × 00 to 0 × 17 and 0 × 40 to 0 × 57
2 × 32	00 to 31	0 × 00 to 0 × 1F and 0 × 40 to 0 × 5F
2 × 40	00 to 39	0 × 00 to 0 × 27 and 0 × 40 to 0 × 67

The 4-row display DDRAM addresses are given in Table 6.4. As can be seen from this table, the second row starts from address 0 × 40, the third row starts from address 0 × 14, and the fourth row starts from address 0 × 54. Two internal controllers are used for 4-row displays.

Table 6.4 4-row display DDRAM addresses.

Display Size	Character Position	DDRAM Address
4 × 16	00 to 15	0 × 00 to 0 × 0F and 0 × 40 to 0 × 4F and 0 × 14 to 0 × 23 and 0 × 54 to 0 × 63
4 × 20	00 to 19	0 × 00 to 0 × 13 and 0 × 40 to 0 × 53 and 0 × 14 to 0 × 27 and 0 × 54 to 0 × 67
4 × ...