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Verify Mode
After programming a chip, it is necessary to verify whether the data are correct.
According to the documentation of the manufacturers about the programming, the
voltage of the pin VCC may vary when the data are verified:
1. VCC(+/- 5%) or VCC(+/- 10%) is used for the verification. If VCC = 5.00V, select
VCC = 5.00V and verify the data once, or select VCC = 4.75V and VCC = 5.25V, and
verify the data twice (+/- 5%), or select VCC=4.50V and VCC=5.50V, and verify the
data twice (+/- 10%).
2. The MinVcc and MaxVcc are used to verify the data. The values of MinVcc and
MaxVcc are provided by the manufacturers.
Buffers
The user may choose to program only part of the chip. This applies to most
E/EPROM (FLASH) devices.
Take the device MACRONIX MX29F200B TSOP48 for example. It is a 16-bit flash
device. Its programmable zone starts at the address 0 and ends at the address 1FFFF
(hexadecimal system). The buffer size (the unit is byte) is (1FFFF+1) * 2 = 40000
(hexadecimal system). Because it is a 16-bit (2 bytes) device, the buffer size is twice
as large as the device size. The default programming method is to program the device
from the start address to the end address. If the user wants to program only the second
half part of the device, change the start address to 10,000 (hexadecimal system) and
