Freescale Semiconductor MPC5200, Application Note, Page: 11 / 20

ATA Interface
MPC5200 ATA Interface, Rev. 0
Freescale Semiconductor 11
b) Write ATA drive device/head register with appropriate DEV
8
bit and LBA bit
c) Wait 400 ns
d) Wait for BSY=0 and DRQ = 0 in ATA drive alternate status register
2. Enable
INTRQ
in ATA drive device control register (nIEN bit)
3. Set PIO mode in ATA drive features register according to non-data command protocol in
ATA/ATAPI-4 spec:
a) Set PIO mode in ATA drive sector count register
b) Write
SET TRANSFER
mode into ATA drive features register
c) Write
SET FEATURES
command into ATA drive device command register
d) Wait for ATA interrupt – indicates that the device has accepted the
SET FEATURES
command
2.9.1.2 MDMA/UDMA Initialization Protocol Steps
1. Select drive according to device selection protocol in ATA/ATAPI-4 spec:
a) Wait for BSY=0 and DRQ = 0 in ATA drive alternate status register
b) Write ATA drive device/head register with appropriate DEV bit and LBA bit
c) Wait 400 ns
d) Wait for BSY=0 and DRQ = 0 in ATA drive alternate status register
2. Enable
INTRQ
in ATA drive device control register (nIEN bit)
3. Set MDMA/UDMA mode in ATA drive features register according to non-data command
protocol in ATA/ATAPI-4 spec:
a) Set MDMA/UDMA mode in ATA drive sector count register
b) Write
SET TRANSFER MODE
into ATA drive features register
c) Write
SET FEATURES
command into ATA drive device command register
d) Wait for ATA interrupt – indicates that the device has accepted the
SET FEATURES
command
8. DEV - The Device Selection bit in ATA drive device/head register specifies which device is selected, 0 or 1.