Literati:Serial Port

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White model #1637287

The Serial port on the White literati model #1637287 is located on the right side of the device seen in the picture on the right. this is also true on the older black models.

currently we do not know where they are on the newer models a picture of a newer model is also on the right and circled is what is believed to be the serial port.

White Model new

the serial port header has the follow pinout from top to bottom:

Number Description
1 5V
2 TX
3 RX

The UART TX and RX signals are at +3.3v TTL level which requires a RS232_Level_Shifter if connecting to a standard RS-232 interface or to a standard USB-to-RS232 adapter. A wide range of USB-to-TTLUART adapters are available including the following:

Once connected this will enable access the bootloader and start up processes of the linux kernel.

Easy Serial Port Access

View of the serial port access
Serial port with back on
Serial cable connected

Use the following items to expose the serial port in a handy way that does not require reopening of the literati to access the serial port:

  • a bit of ribbon cable
  • male header pins
  • female socket

another option includes the use of a 1/8" audio jack which can be easily mounted by drilling a hole in the back cover.

Using CA-42 Serial Cable

CA-42 USB Serial Cable
CA-42 Pinout
CA-42 Cut Open

One of the simplest way to connect your PC to the Literati serial port is to order a Nokia CA-42 Data Cable from DealExtreme. When you receive it, you can cut it open to find 3 or 4 wires depending on the revision. If you have three wires, then you will find GND, RX, and TX. If you have four wires, then the fourth wire is +3.3V. The example CA-42 only has three. The cable can be soldered to a female pin header so it can connect to the male pins used to expose the serial port to the outside.

Boot Loader

during the boot process there is a 3 second count down to allow a user to enter the bootloader before booting the kernel.

To get out of the bootloader right now you type "reset" and the device will reboot allowing you to get out of the bootcmd line there is a way to boot from nand but iv forgot to log the offsets.

Boot CMD's

boot zImage from sd that fat32 part
boot zImage from sd that fat32 part
boot zImage from sd that fat32 part
boot zImage from sd that fat32 part
?       - alias for 'help'
base    - print or set address offset
bdinfo  - print Board Info structure
bootm   - boot application image from memory
branch  - enable or disable branch prediction
TestMemory      - start application at address 'addr'
cmp     - memory compare
cp      - memory copy
crc32   - checksum calculation
dcache  - enable or disable data cache
dnw     - initialize USB device and ready to receive for Windows server (specific)
echo    - echo args to console
erase   - erase FLASH memory
exit    - exit script
flinfo  - print FLASH memory information
go      - start application at address 'addr'
help    - print online help
icache  - enable or disable instruction cache
imls    - list all images found in flash
itest   - return true/false on integer compare
loadb   - load binary file over serial line (kermit mode)
loads   - load S-Record file over serial line
loady   - load binary file over serial line (ymodem mode)
loop    - infinite loop on address range
md      - memory display
mm      - memory modify (auto-incrementing)
movi    - moviNAND sub-system
mtest   - simple RAM test
mw      - memory write (fill)
nand    - NAND sub-system
nboot   - boot from NAND device
nm      - memory modify (constant address)
printenv- print environment variables
protect - enable or disable FLASH write protection
reset   - Perform RESET of the CPU
saveenv - save environment variables to persistent storage
setenv  - set environment variables
sleep   - delay execution for some time
test    - minimal test like /bin/sh
version - print monitor version
1 update boot from sd 
2 update kernel from sd 
3 update resource from sd 
4 update all