Samsung S5PC100 User Manual page 517

CF CONTROLLER
2.2 MISC
2.2.1 nCSEL
The nCSEL is card selection pin. This signal internally pulled-up in CF/CF+ card. This configures the device as a
Master or a Slave if configured in the True-IDE mode. If this pin is grounded, this device is configured as a Master.
If this pin is open, this device is configured as a Slave. This signal must be tied GND or VCC, not pulled-up/
pulled-down. If you pulled down this signal on board, nCSEL voltage level is not stable because this signal
internally pulled-up in CF/CF+ card.
2.3 EXTERNAL PULL-UP/ PULL-DOWN
Pull-up to VCC
nIREQ ( R ≥ 10KΩ )
nWAIT ( R ≥ 10KΩ )
nIOIS16 ( R ≥ 10KΩ )
nCD ( R ≥ 10KΩ )
Figure 5.5-16 External (External of SOC) Glue Logic for Card Detection Pin
5.5-22
Table 5.5-7 Externally Pull-Up/Pull-Down Signals
OR Gate
nCD_CF
S5PC100 USER'S MANUAL (REV1.0)
Pull-down to GND
nINPACK ( R ≥ 5.6KΩ )
VCC VCC
CF Card
nCD0
nCD1