User's Manual

DRAFT
4: VAM-CM interfaces
Pin Signal Description
#21 VBUS Supply voltage, 5,5V max
#23 Dp Digital data
#25 Dm Digital data
#27 GND Signal GND
Table 3. System USB interface pins
4.2.2:USIM interface description
The USIM interface provides USIM interface from the VAM-CM to VAM terminal for easier user
access.
The USIM reader in VAM terminal should be placed so that trace length from VAM control interface to
USIM reader shall not exceed 300mm.
USIM interface signals are located in VAM Control interface as described in Table 4 .
Pin Signal In/out Description
#26 SIM_V Out Supply voltage for SIM.
#28 SIM_RST Out Digital data
#30 SIM_CLK Out Digital clock
#32 SIM_IO In/Out Digital data
#34 Card detect In "HIGH" (Float) = Card not present
"LOW" = Card present
#36 SIM_GND Signal GND
Table 4. USIM interface pins
4.2.3:VAM control UART interface description
The VAM control UART interface provides for VAM terminal to control VAM-CM features. The UART
interface is connected via level shifter circuit which allows VAM terminal to determine the signal
voltage level using V_io pin in VAM-CM system connector.
The UART control interface is the default control interface for VAM-CM. The Control interface can be
changed to USB using VAM Boot selector ( Table 9 ).
VAM control UART interface signals are located in VAM Control interface as described in Table 5 .
VAM-CM is using 2-wire UART interface with TXD, RXD signals. VAM_CM_WAKEUP and VAM_CM_
SLEEP signals is used to wake up CM from sleep state (low power mode) and to get CM sleep state
status, refer VAM-CM UART interface PM Handling on page 20 section for CM low power
(Sleep state) handling
Pin Signal In/Out Description
#16 TXD Out UART transmit data
#18 RXD In UART receive data
#24 GND UART GND
Table 5. VAM control UART interface pins
13:GSPS Core Module 2.0 VAM-CM HW Description
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