User guide
18 CY3687 MoBL-USB FX2LP18 Development Kit User Guide, Doc. # 001-68582 Rev. *B
Development Board
U11 is used only for converting the I
2
C signals to RS-232 for running the Keil debugger. It is not used
for USB access. U12 converts the 3.3 V 8051 serial port signals to bipolar RS-232 levels. U13 con-
tains the I
2
C to RS-232 conversion program. U13 is not intended to be user-programmable.
Six 20-pin headers, P1-P6, provide interface signals to the plug-in prototyping board supplied in this
kit, as well as serving as connection points for HP(Agilent) logic analyzer pods. P8 contains a subset
of signals from P1-P6 on a connector that is pinned out for connection to a ‘straight- through’ ATA
cable. Two slide switches, SW1 and SW2, control the connection and selection of the three socketed
EEPROMS at U5, U7, and U8.
3.3 Jumpers
Table 3-1. Jumper Settings
Jumper Function Default Notes
JP1
Current measurement
point for VCCIO
IN (1-2)
This jumper may be removed and replaced with ammeter
probes in series to measure current for this supply.
JP2
Current measurement
point for VCCORE
IN (1-2)
This jumper may be removed and replaced with ammeter
probes in series to measure current for this supply.
JP3 Removed This jumper has been removed from the schematic
JP4
Current measurement
point for AVCC
IN (1-2)
This jumper may be removed and replaced with ammeter
probes in series to measure current for this supply.
JP5 Board power source IN (1-2)
If this jumper is in place, the board is bus-powered from the
USB connector (J2). If this jumper is removed, the board must
be powered via JP5.1 or another 5v jumper.
JP6 SAFE_WP IN (1-2)
Removing this jumper allows the SAFE EEPROM to be repro-
grammed. Reprogramming the SAFE EEPROM is not recom-
mended. If the SAFE EEPROM contents are lost, the
EEPROMs cannot be reprogrammed via USB.
JP7 EEPROM WP PA7 (1-2)
This jumper selects the WP input for the ‘normal’ EEPROMs.
Position 1-2 ties WP to PA7. In this position, PA7 must be
driven low to reprogram the EEPROM. The Cypress program-
ming tools will drive PA7 low during programming. If PA7 is
used by your application, you can remove this jumper during
normal use and move it to position (2-3) during EEPROM pro-
gramming.
JP8
Current measurement
point or alter-nate
power input for 3.3 V
supply
IN (1-2)
This jumper may be removed and replaced with ammeter
probes in series to measure current for this supply. This point
may be used to provide an external source for the 3.3 V supply.