Rainbow Electronics АТ89С2051 - Manual (Page 7)

AT89C2051
7
Notes: 1. The internal PEROM address counter is reset to 000H on the rising edge of RST and is advanced by a positive pulse at
XTAL 1 pin.
2. Chip Erase requires a 10 ms PROG pulse.
3. P3.1 is pulled Low during programming to indicate RDY/BSY.
Figure 3. Programming the Flash Memory Figure 4. Verifying the Flash Memory
Flash Programming Modes
Mode RST/VPP P3.2/PROG P3.3 P3.4 P3.5 P3.7
Write Code Data (1)(3) 12V L H H H
Read Code Data (1) H H L L H H
Write Lock Bit - 1 12V H H H H
Bit - 2 12V H H L L
Chip Erase 12V H L L L
Read Signature Byte H H L L L L
(2)
PP