1. are you handwiring or trying to use the existing pcb for the matrix?
2. if it has a plate, and you're keeping the plate, it might be easier to handwire. (not really as scary as it sounds)
3. what TKL do you have?
- you have to define the electrical matrix as well as the physical matrix
physical will look something like this (which is transposed from the electrical matrix below)
#define LAYOUT_tkl_iso( \
k00, k02, k03, k04, k05, k06, k07, k08, k09, k0A, k0B, k0C, k0D, k0E, k0F, k0G, \
k01, k10, k11, k12, k13, k14, k15, k16, k17, k18, k19, k1A, k1B, k1D, k1E, k1F, k1G, \
k20, k21, k22, k23, k24, k25, k26, k27, k28, k29, k2A, k2B, k2C, k2E, k2F, k2G, \
k30, k31, k32, k33, k34, k35, k36, k37, k38, k39, k3A, k3B, k3C, k3D, \
k40, k41, k42, k43, k44, k45, k46, k47, k48, k49, k4A, k4B, k4D, k4F, \
k50, k51, k52, k57, k5A, k5B, k5C, k5D, k5E, k5F, k5G \
)
electrical will look something like this:
{ \
{ k00, k01, k02, k03, k04, k05, k06, k07, k08, k09, k0A, k0B, k0C, k0D, k0E, k0F, k0G }, \
{ k10, k11, k12, k13, k14, k15, k16, k17, k18, k19, k1A, k1B, XXX, k1D, k1E, k1F, k1G }, \
{ k20, k21, k22, k23, k24, k25, k26, k27, k28, k29, k2A, k2B, k2C, XXX, k2E, k2F, k2G }, \
{ k30, k31, k32, k33, k34, k35, k36, k37, k38, k39, k3A, k3B, k3C, k3D, XXX, XXX, XXX }, \
{ k40, k41, k42, k43, k44, k45, k46, k47, k48, k49, k4A, k4B, XXX, k4D, XXX, k4F, XXX }, \
{ k50, k51, k52, XXX, XXX, XXX, XXX, k57, XXX, XXX, k5A, k5B, k5C, k5D, k5E, k5F, k5G } \
}
...taken from the phantom tkl
keyboardname.h is the matrix stuff like code above
keyboardname.c is very little of the config stuff, most is in config.h
if you're a trackpoint fan, check out
https://tex.com.tw/and there was this too... modified tipro
https://deskthority.net/viewtopic.php?f=8&t=4214&start=