AT91SAM7S32-AI ATMEL [ATMEL Corporation], AT91SAM7S32-AI Datasheet - Page 238

• Manufacturer Part Number: AT91SAM7S32-AI
• Description: AT91 ARM Thumb-based Microcontrollers
• Manufacturer: ATMEL [ATMEL Corporation]

• PCS: Peripheral Chip Select
This field is only used if Fixed Peripheral Select is active (PS = 0).
If PCSDEC = 0:
If PCSDEC = 1:
• DLYBCS: Delay Between Chip Selects
This field defines the delay from NPCS inactive to the activation of another NPCS. The DLYBCS time guarantees non-over-
lapping chip selects and solves bus contentions in case of peripherals having long data float times.
If DLYBCS is less than or equal to six, six MCK periods (or 6*N MCK periods if FDIV is set) will be inserted by default.
Otherwise, the following equation determines the delay:
If FDIV is 0:
If FDIV is 1:
238
PCS = xxx0
PCS = xx01
PCS = x011
PCS = 0111
PCS = 1111
(x = don’t care)
NPCS[3:0] output signals = PCS.
AT91SAM7S32 Preliminary
Delay Between Chip Selects
Delay Between Chip Selects
NPCS[3:0] = 1110
NPCS[3:0] = 1101
NPCS[3:0] = 1011
NPCS[3:0] = 0111
forbidden (no peripheral is selected)
=
=
DLYBCS
---------------------- -
DLYBCS
-------------------------------- -
MCK
MCK
N
6071A–ATARM–28-Oct-04