Problem with H4 not booting (zChris's board)

[exxos]

Just to be sure you're not using a DIP CPU *AND* a PLCC CPU ?

[zChris]

Yeah, only have 1 CPU and thats PLCC.

/zChris

[exxos]

Yeah, only have 1 CPU and thats PLCC.

The image shows DIP CPU ?

[rubber_jonnie]

Yeah, only have 1 CPU and thats PLCC.

The image shows DIP CPU ?

I'm in agreement, the photo shows a DIP CPU present.

[zChris]

Ah alright, then its DIP.

/zChris

[zChris]

Alright, have done some measuring of frequency today. All the chips had signals present except MMU where i could not read a signal on Pin5 (16Mhz) and on Pin 19 and 20 it fluctuated between 2 and 4 Mhz. The measuring was done with the reset button NOT pressed in if that matters.

/zChris

[zChris]

After looking at https://www.exxosforum.co.uk/forum/viewt ... f=31&t=149 i saw that it was different pins on the SMD version of MCU (MMU) so after measuring again it i have found 4Mhz , 8Mhz and 16Mhz on that one aswell.

/zChris

[exxos]

You need to check ROM0,1,2 on the GLUE after reset .. But you need to put your scope in a one shot mode. I don't remember of hand where the setting is but without it you might miss the signals as they are very fast.

[zChris]

Alright, what am i looking for on those lines ?

/zChris

[exxos]

Alright, what am i looking for on those lines ?

/zChris

They should be pulsing low. IIRC ROM should pulse first after reset.