Datasheet

41
3286P–MICRO–3/10
AT89S8253
Notes: 1. See detailed timing for Serial Programming Mode.
2. Internally timed for 8.0 ms.
3. Internally timed for 8.0 ms. Programming begins 150 µs (minimum) after the last write pulse.
4. P3.0 is pulled low during programming to indicate RDY/BSY
5. 1 to 64 bytes can be programmed at a time per page.
6. 1 to 32 bytes can be programmed at a time per page.
7. Fuse Definitions:
Fuse1 (Serial Programming Fuse): This fuse enables/disables the serial programming mode (ISP).
Fuse2 (x2 Mode Selection Fuse): This fuse enables/disables the internal x2 clock mode.
25. Flash and EEPROM Parallel Programming Modes
Mode RST PSEN
ALE
EA
P3.3 P3.4 P3.5 P3.6 P3.7
Data I/O
P0.7:0
Address
P2.5:0,
P1.7:0
Serial Prog. Modes
(1)
Hh h
Chip Erase
(2)
H L 1.0 µs 12V H L H L L X X
Page Write
(3)(4)(5)
12K Code H L 1.0 µs 12VLHHHH DI ADDR
Read 12K Code H L H 12V L L H H H DO ADDR
Page Write
(3)(4)(6)
2K Data H L 1.0 µs 12V L H L H H DI ADDR
Read 2K Data H L H 12V L L L H H DO ADDR
Write Lock Bits
(2)(4)
Bit - 1
H L 1.0 µs 12V H L H H L
D0 = 0 X
Bit - 2 D1 = 0 X
Bit - 3 D2 = 0 X
Read Lock Bits
Bit - 1
H L H 12V H H H L L
D0 X
Bit - 2 D1 X
Bit - 3 D2 X
Page Write
(3)(4)(5)
User Row H L 1.0 µs 12V H L H H H DI 0 - 3FH
Read User Row H L H 12V L L H L H DO 0 - 3FH
Read Sig. Row H L H 12V L L H L L DO 0 - 3FH
Write
Fuse
(2)(4)(7)
Fuse1
SerialPrgEn
H L 1.0 µs 12V L H H L H
D0 = 0 X
SerialPrgDis D0 = 1 X
Fuse2
x2 ClockEn D1 = 0 X
x2 ClockDis D1 = 1 X
Fuse3
UsrRowPrgEn D2 = 0 X
UsrRowPrgDis D2 = 1 X
Fuse4
External Clock En D3 = 0 X
Crystal Clock En D3 = 1 X
Read Fuse
SerialPrg (Fuse1)
H L H 12V H H H L H
D0 X
x2 Clock (Fuse2) D1 X
UsrRow Prg
(Fuse3)
D2 X
Clock Select
(Fuse4)
D2 X
}
}
}
}