MyOldPCS

I continue to explore CH32V microcontrollers. Today, I have the tiny CH32V003J4M6 in a SOP-8 package on my desk.   This is the smallest package with a bare minimum of pins — 2 are for power, leaving 6 available for use. It doesn’t even have a hardware reset pin (NRST). Like other microcontrollers in the CH32V00x series, it is programmed via a single SWIO wire ( pin 8 ). And here lies an interesting problem: if you initialize this pin in your firmware for other tasks, it stops working as SWIO. After that, programming the chip using the standard method becomes impossible. For example, the following code prints “Hello world” to the UART: #include <ch32v00x.h> #include <debug.h> void NMI_Handler ( void ) __attribute__ (( interrupt ( "WCH-Interrupt-fast" ))); void HardFault_Handler ( void ) __attribute__ (( interrupt ( "WCH-Interrupt-fast" ))); int main ( void ) { SystemCoreClockUpdate (); Delay_Init (); USART_Printf_Init ( 96...

I received a large batch of CH32V203C8T6 microcontrollers. And a question arose: how do I check if these microcontrollers are good? There are no ready-made device boards available at the moment, but they still need to be tested somehow. Fortunately, I have a few LQFP48 to PGA adapter boards. I haven’t had to solder such complex chips before. I’ll try using a mini-oven for the soldering process. Additionally, I’ll need solder paste. I have a tube that has been sitting around for quite a while. I once tried it on some small parts and put it aside, thinking that one day I’d be soldering serious stuff and this paste would come in handy. Several years have passed, and that moment has come. But as it turns out, solder paste can dry up, especially if the tube isn’t sealed tightly :) It used to be almost liquid, but now it feels like playdough. I managed to squeeze some out and smear it across the adapter. This is my first time soldering packages like this, let alone using bottom heating...