J
Jeff M.
- Jan 1, 1970
- 0
Hi, I am trying to get the Shane Tolmie v9.30 bootloader working with
my PIC 16F877A @ 20MHz and am encountering some strange problems. I am
able to program the bootloader into the chip no problem. When I try to
load the test program, I keep getting a "writing error". I sometimes
also get a communication timeout error, but this is much less frequent.
I keep doing this and eventually, I am able to complete the programming
successfully. When it fails, which is most of the time, it fails at
random points during the download. I have confirmed this same behavior
on a second chip I have.
In despiration, I tried this same experiment with the Tiny Bootloader
and had the same issue, fail most of the time, work once in awile. I
looked at my serial cable on a Scope and it looked ok. If anything, the
RS-232 data from the PC looked real good. The RS-232 data from the PIC
was not ideal, its peak to peak swing was about 3 volts lower then
expected. Also, the signals had a slope on them. The little I know
about RS-232, my signal should be well within the operating range.
Is there any debug commands in the windows bootloader software I can
use to further isolate this problem? Does anyone have any thoughts on
what this could be? Thanks for your help.
my PIC 16F877A @ 20MHz and am encountering some strange problems. I am
able to program the bootloader into the chip no problem. When I try to
load the test program, I keep getting a "writing error". I sometimes
also get a communication timeout error, but this is much less frequent.
I keep doing this and eventually, I am able to complete the programming
successfully. When it fails, which is most of the time, it fails at
random points during the download. I have confirmed this same behavior
on a second chip I have.
In despiration, I tried this same experiment with the Tiny Bootloader
and had the same issue, fail most of the time, work once in awile. I
looked at my serial cable on a Scope and it looked ok. If anything, the
RS-232 data from the PC looked real good. The RS-232 data from the PIC
was not ideal, its peak to peak swing was about 3 volts lower then
expected. Also, the signals had a slope on them. The little I know
about RS-232, my signal should be well within the operating range.
Is there any debug commands in the windows bootloader software I can
use to further isolate this problem? Does anyone have any thoughts on
what this could be? Thanks for your help.