MC9S12KG128 Datasheet, PDF (131/600 Pages) Freescale Semiconductor, Inc – Microcontrollers

START
Chapter 3 2 Kbyte EEPROM Module (EETS2KV1)
Tbus ≤ 1 µs?
NO
PROGRAM/ERASE IMPOSSIBLE
yes
PRDIV8 = 0 (reset)
OSCILLATOR
NO
CLOCK
> 12.8 MHz?
yes
PRDIV8 = 1
PRDCLK = oscillator clock/8
PRDCLK = oscillator clock
PRDCLK[MHz]*(5+Tbus[µs])
an integer?
YES
NO
EDIV[5:0] = INT(PRDCLK[MHz]*(5+Tbus[µs]))
EDIV[5:0] = PRDCLK[MHz]*(5+Tbus[µs])-1
TRY TO DECREASE Tbus
EECLK = (PRDCLK)/(1+EDIV[5:0])
1/EECLK [MHz] + Tbus[ms] ≥5
AND
EECLK > 0.15 MHz
?
NO
YES
END
YES
EDIV[5:0] ≥ 4?
NO
PROGRAM/ERASE IMPOSSIBLE
Figure 3-17. PRDIV8 and EDIV Bits Determination Procedure
MC9S12KG128 Data Sheet, Rev. 1.15
Freescale Semiconductor
131