propeller-load ignored bytes?

SRLM

Sometimes when i download a program the propeller-load ignores some bytes:

... <compiler messages>
Ignored 37 bytes. 
Propeller Version 1 on /dev/ttyUSB0
Ignored 63 bytes. 
Loading main.elf to EEPROM via hub memory
18668 bytes sent                  
Verifying RAM ... OK
Programming EEPROM ... OK
Verifying EEPROM ... OK
[ Entering terminal mode. Type ESC or Control-C to exit. ]

Sometimes the bytes are ignored, and sometimes they are not. If I immediately re-run the program, it downloads without ignoring bytes:

... <compiler messages>
Propeller Version 1 on /dev/ttyUSB0
Loading main.elf to EEPROM via hub memory
18668 bytes sent                  
Verifying RAM ... OK
Programming EEPROM ... OK
Verifying EEPROM ... OK
[ Entering terminal mode. Type ESC or Control-C to exit. ]

In both cases it's downloading the same amount (apparently), and it seems to work correctly in both cases. What's happening here?

David Betz

SRLM wrote: »

Sometimes when i download a program the propeller-load ignores some bytes:

... <compiler messages>
Ignored 37 bytes. 
Propeller Version 1 on /dev/ttyUSB0
Ignored 63 bytes. 
Loading main.elf to EEPROM via hub memory
18668 bytes sent                  
Verifying RAM ... OK
Programming EEPROM ... OK
Verifying EEPROM ... OK
[ Entering terminal mode. Type ESC or Control-C to exit. ]

Sometimes the bytes are ignored, and sometimes they are not. If I immediately re-run the program, it downloads without ignoring bytes:

... <compiler messages>
Propeller Version 1 on /dev/ttyUSB0
Loading main.elf to EEPROM via hub memory
18668 bytes sent                  
Verifying RAM ... OK
Programming EEPROM ... OK
Verifying EEPROM ... OK
[ Entering terminal mode. Type ESC or Control-C to exit. ]

In both cases it's downloading the same amount (apparently), and it seems to work correctly in both cases. What's happening here?

Is this on a QuickStart board? The "ignoring bytes" code was added to get around a problem with QuickStart not having a pullup on the RX line. It doesn't mean that bytes from your program are being ignored. It means that garbage during the initial handshake with the ROM loader is being ignored.

SRLM

David Betz wrote: »

Is this on a QuickStart board? The "ignoring bytes" code was added to get around a problem with QuickStart not having a pullup on the RX line. It doesn't mean that bytes from your program are being ignored. It means that garbage during the initial handshake with the ROM loader is being ignored.

It's on a custom board, but I did use the QuickStart and Eddie schematics as the base for my FTDI circuit, along with the buffer from a PhiPi post:


Sometimes when I run my program with the -t option, I notice a bit of garbage at the beginning of the terminal output, but then it never reappears. Is this related? And the fix is a pullup on RX?

David Betz

SRLM wrote: »

It's on a custom board, but I did use the QuickStart and Eddie schematics as the base for my FTDI circuit, along with the buffer from a PhiPi post:


Sometimes when I run my program with the -t option, I notice a bit of garbage at the beginning of the terminal output, but then it never reappears. Is this related? And the fix is a pullup on RX?

Looks like you already have a pullup on RX. Anyway, this is a point of disagreement. Some people think that the pullup should not be necessary and, in fact, it can get in the way of making more general use of P31. This is why the "ignoring bytes" feature was added to propeller-load. I think the Propeller Tool loader does something similar.

Edit: oops. I suppose I really meant a pullup on TX? I'm not a hardware guy. Sorry for the confusion!

jazzed

I would have called them garbage bytes, but I'd rather not mention garbage (exhale) and propeller in the same breath.

The pull up needs to be on U12 pin 3.