AT89S8252-16JA ATMEL [ATMEL Corporation], AT89S8252-16JA Datasheet - Page 26

• Manufacturer Part Number: AT89S8252-16JA
• Description: 8-Bit Microcontroller with 8K Bytes Flash
• Manufacturer: ATMEL [ATMEL Corporation]

Serial Programming
Instruction
Instruction Set
Notes:
26
Instruction
Programming Enable
Chip Erase
Read Code Memory
Write Code Memory
Read Data Memory
Write Data Memory
Write Lock Bits
1. DATA polling is used to indicate the end of a byte write cycle which typically takes less than 2.5 ms at 5V.
2. “aaaaa” = high order address.
3. “x” = don’t care.
AT89S8252
1010 1100
1010 1100
aaaa a001
aaaa a010
00aa a101
00aa a110
1010 1100
Byte 1
The Instruction Set for Serial Programming follows a 3-byte protocol and is shown in the
following table:
Input Format
0101 0011
xxxx x100
low addr
low addr
low addr
low addr
Byte 2
x x111
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
Byte 3
data in
data in
Operation
Enable serial programming interface after RST goes high.
Chip erase both 8K & 2K memory arrays.
Read data from Code memory array at the selected address.
The 5 MSBs of the first byte are the high order address bits.
The low order address bits are in the second byte. Data are
available at pin MISO during the third byte.
Write data to Code memory location at selected address. The
address bits are the 5 MSBs of the first byte together with the
second byte.
Read data from Data memory array at selected address. Data
are available at pin MISO during the third byte.
Write data to Data memory location at selected address.
Write lock bits.
Set LB1, LB2 or LB3 = “0” to program lock bits.
0401F–MICRO–11/03