Sxcnfg Bit Definitions - Intel PXA255 Developer's Manual

Table 6-13. SXCNFG Bit Definitions (Sheet 1 of 4)
0x4800_001C
Bit 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9
Reset 0 0 0 0 0 0
Bits Name
31
30 SXLATCH2
29:28 SXTP2
27:26 SXCA2
25:24 SXRA2
23:21 SXRL2
Intel® PXA255 Processor Developer's Manual
SXRL2 SXCL2
0 0 0 0 0 0 0
— reserved
SXMEM latching scheme for pair 2/3
0 – Latch return data with fixed delay on MEMCLK
1 – Latch return data with return clock
Must be set to a 1 to enable the return clock SDCLK for latching data. For more details on
this return data latching, see
SX Memory type for partition pair 2/3
00 – Synchronous Mask ROM (SMROM)
01 – reserved
10 – non-SDRAM-like Synchronous Flash
11 – reserved
SX Memory column address bit count for partition pair 2/3
00 – 7 column address bits
01 – 8 column address bits
10 – 9 column address bits
11 – 10 column address bits
SX Memory row address bit count for partition pair 2/3
00 – 12 row address bits
01 – 13 row address bits
10 – reserved
11 – reserved
RAS Latency for SX Memory partition pair 2/3.
Number of external SDCLK cycles between receiving the ACT command and the READ
command. The unit size for SXRL2 is the external SDCLK cycle.
IF SXTP2 = "00" (SMROM):
000 – 1 clock
001 – 2 clocks
010 – 3 clocks
011 – 4 clocks
100 – 5 clocks
101 – 6 clocks
110 – 7 clocks
111 – 8 clocks
IF SXTP2 = 10 (non-SDRAM timing Fast Flash), this field is not used and must be
programmed to 111.
SXCNFG
0 0 0 0 * * * *
Description
Section 6.5.4.
Memory Controller
Memory Controller
8 7 6 5 4 3
SXRL0 SXCL0
* * * * * * * *
2 1 0
* 0 *
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