cs5535 National Semiconductor Corporation, cs5535 Datasheet - Page 505

• Manufacturer Part Number: cs5535
• Description: Geode Cs5535 Companion Multi-function South Bridge
• Manufacturer: National Semiconductor Corporation

Revision 0.8
Flash Controller Register Descriptions
NOR Flash Timing for Chip Selects 2 and 3 (NORTF_T23)
MSR Address
Type
Reset Value
Note 1.
5.19.1.3
MSR Address
Type
Reset Value
Most NAND devices have similar timing. All NAND devices share the timing registers. The valid range for the count values
of setup time and hold time in NAND MSRs is 0 through 7 Local Bus clock (‘lb_c’) cycles or LPC clock (‘lpc_c’) cycles and
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10
31:27
26:24
22:20
18:16
15:11
10:8
Bit
6:4
2:0
23
19
7
3
RSVD
General Purpose device is used (with NOR Controller). If signal FLASH_IOCHRDY is not used by the General Pur-
pose device, then the valid range for the count value of pulse width in NOR MSR registers is 1 through 7. If
FLASH_IOCHRDY is used by the General Purpose device, then the valid range for the count value of pulse width
in NOR MSR registers is 2 through 7. In the case of NOR devices, as NOR Controller doesn’t support the use of
FLASH_IOCHRDY (explained in Section 4.18.2 "NOR Flash Controller/General Purpose Chip Select" on page
171),the valid range for the count values of setup time, pulse width, and hold time in NOR MSR registers is 1
through 7.In the case of NOR Controller’s WE# and RE# strobe pulse widths, if NOR Control MSR register bits[7:4]
(CHKRDY[3:0]) are enabled (active high) in the case of General Purpose devices then the generated pulse widths
will be longer than programmed count value. If setup or hold time in NOR MSR registers is programmed as 0, then
the NOR Controller’s WE# and RE# generation will use 16 as the count value of NOR setup or hold time.
The valid range for the count values of setup time, and hold time in NOR MSR registers is 1 through 7 when a
NAND Flash Data Timing MSR (NANDF_DATA)
Name
RSVD
tH3 (Note 1)
RSVD
tP3
RSVD
tS3 (Note 1)
RSVD
tH2 (Note 1)
RSVD
tP2
RSVD
tS2 (Note 1)
5140001Ah
R/W
07770777h
5140001Bh
R/W
07770777h
tH3
Description
Reserved. Reads return value written.
Hold Time for NOR Chip Select 3. Hold from WE# or RE# rising edge to chip select.
Refer to Figure 4-58 "NOR Flash with Wait States Timing" on page 173.
Reserved. Reads return value written.
Strobe Pulse Width for NOR Chip Select 3. RE# and WE# strobe pulse width. At the
end of the tP, sample the FLASH_ IOCHRDY signal to see if a wait state is needed.
Refer to Figure 4-58 "NOR Flash with Wait States Timing" on page 173.
Reserved. Reads return value written.
Setup Time for NOR Chip Select 3. Chip select to WE# or RE# falling edge setup
time. Refer to Figure 4-58 "NOR Flash with Wait States Timing" on page 173.
Reserved. Reads return value written.
Hold Time for NOR Chip Select 2. Hold from WE# or RE# rising edge to chip select.
Refer to Figure 4-58.
Reserved. Reads return value written.
Strobe Pulse Width for NOR Chip Select 2. RE# and WE# strobe pulse width. At the
end of the tP, sample the FLASH_IOCHRDY signal to see if a wait state is needed.
Refer to Figure 4-58 "NOR Flash with Wait States Timing" on page 173.
Reserved. Reads return value written.
Setup Time for NOR Chip Select 2. Chip select to WE# or RE# falling edge setup
time. Refer to Figure 4-58 "NOR Flash with Wait States Timing" on page 173.
tP3
NORTF_T23 Bit Descriptions
NORTF_T23 Register Map
tS3
(Continued)
505
RSVD
tH2
9
8
7
6
tP2
5
4
3
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2
tS2
1
0