Screen as a serial terminal - Raspberry Pi Forums

i've connected usb serial cable assembly sold adafruit (http://www.adafruit.com/products/954) mac , pi.
i'm trying use screen terminal to upload files dwelch67's bootloader05 (https://github.com/dwelch67/raspberrypi ... otloader05). don't seem know i'm doing. i've don in former life, though.

screen /dev/tty.pl2303-00004126 115200

@ point i'm stuck. thought should able issue upload command using sx, screen seems hung.

i never seem make progress until make post asking question.

1) disconnect power raspberry pi.
2) connect usb-to-serial raspberry pi: ground, tx , rx.
3) plug usb-to-serial computer
4) type "ls /dev/tty.*" , identify usb-to-serial device
5) type, example, "screen /dev/tty.pl2303-00004326 115200"
6) connect power raspberry pi.
7) notice numbers received on display raspberry pi.
8) issue upload command using ctrl-a followed ": sx -kb blinker.bin"

i'm stuck because transfer failing:transfer incomplete
sending blinker.bin, 1 blocks: give local xmodem receive command now.
xmodem sectors/kbytes sent: 0/ 0kretry 0: nak on sector
xmodem sectors/kbytes sent: 1/ 0kretry 0: nak on sector
retry 0: nak on sector
retry 0: nak on sector
retry 0: nak on sector
retry 0: nak on sector
retry 0: nak on sector
retry 0: nak on sector
retry 0: nak on sector
retry 0: nak on sector
retry 0: nak on sector
retry 0: nak on sector
retry 0: retry count exceeded

transfer incomplete

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