MPC555
/
MPC556
CDR MoneT FLASH EEPROM
MOTOROLA
USER’S MANUAL
Rev. 15 October 2000
19-8
Table 19-3 CMFTST Bit Descriptions
Bit(s)
Name
Description
0:19
—
Reserved
20
NVR
Negative voltage range. This bit switches between the low and high voltage range of the nega-
tive charge pump in programming and erasing the CMF Flash module when GDB = 0b1. This
bit is writeable when HVS = 0b0.
0 = High Range (more negative)
1 = Low Range
21:23
PAWS
[0:2]
Program amplitude/width modulation select. The PAWS bits, in conjunction with the NVR and
GDB bits can be used to select the programming voltage applied to the drain or gate of the EE-
PROM bitcell. These bits should be left set to 0b000, unless advised by Motorola. For informa-
tion about PAWS programming modes, see
and
24
—
Reserved
25
STE
This bit is reserved for Motorola factory testing and should always be programmed to 0b0.
0 = Normal Operation
1 = Factory test mode use only. This setting could disturb contents of flash.
26
GDB
Gate/drain bias select. This bit works in conjunction with the PAWS bits to select between pos-
itive and negative ramped voltages for programing and erasing. This bit is writeable when SES
= 0b0.
0 = Positive voltage ramp selected on the bitcell drain.
1 = Negative voltage ramp selected on the bitcell gate.
27:31
—
Reserved
Table 19-4 CMF Programming Algorithm (v6 and Later)
No. of Pulses
Pulse Width
NVR
PAWs
GDB
PAWs
Mode
Description
4
256
µ
s
1
100
1
Mode 4NL
Negative gate ramp (low range)
4
256
µ
s
1
101
1
Mode 5NL
4
256
µ
s
1
110
1
Mode 6NL
4
256
µ
s
1
111
1
Mode 7NL
20
50
µ
s
0
100
1
Mode 4NL
Negative gate ramp (high range)
20
50
µ
s
0
101
1
Mode 5NL
20
50
µ
s
0
110
1
Mode 6NL
max. 48,000
50
µ
s
0
111
1
Mode 7NL
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Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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